Bug 852428 part 2. Make nsIFrame::Init infallible. r=dholbert

layout/base/nsCSSFrameConstructor.cpp

@@ -4549,14 +4549,12 @@ nsCSSFrameConstructor::InitAndRestoreFrame(const nsFrameConstructorState& aState
   NS_PRECONDITION(mUpdateCount != 0,
                   "Should be in an update while creating frames");
   
-  nsresult rv = NS_OK;
-  
   NS_ASSERTION(aNewFrame, "Null frame cannot be initialized");
   if (!aNewFrame)
     return NS_ERROR_NULL_POINTER;
 
   // Initialize the frame
-  rv = aNewFrame->Init(aContent, aParentFrame, aPrevInFlow);
+  aNewFrame->Init(aContent, aParentFrame, aPrevInFlow);
   aNewFrame->AddStateBits(aState.mAdditionalStateBits);
 
   if (aState.mFrameState) {
@@ -4569,7 +4567,7 @@ nsCSSFrameConstructor::InitAndRestoreFrame(const nsFrameConstructorState& aState
     CountersDirty();
   }
 
-  return rv;
+  return NS_OK;
 }
 
 already_AddRefed<nsStyleContext>

layout/forms/nsComboboxControlFrame.cpp

@@ -1371,12 +1371,7 @@ nsComboboxControlFrame::CreateFrameFor(nsIContent*      aContent)
     return nullptr;
   }
 
-  nsresult rv = mDisplayFrame->Init(mContent, this, nullptr);
+  mDisplayFrame->Init(mContent, this, nullptr);
-  if (NS_FAILED(rv)) {
-    mDisplayFrame->Destroy();
-    mDisplayFrame = nullptr;
-    return nullptr;
-  }
 
   // Create a text frame and put it inside the block frame
   nsIFrame* textFrame = NS_NewTextFrame(shell, textStyleContext);
@@ -1385,14 +1380,7 @@ nsComboboxControlFrame::CreateFrameFor(nsIContent*      aContent)
   }
 
   // initialize the text frame
-  rv = textFrame->Init(aContent, mDisplayFrame, nullptr);
+  textFrame->Init(aContent, mDisplayFrame, nullptr);
-  if (NS_FAILED(rv)) {
-    mDisplayFrame->Destroy();
-    mDisplayFrame = nullptr;
-    textFrame->Destroy();
-    textFrame = nullptr;
-    return nullptr;
-  }
   mDisplayContent->SetPrimaryFrame(textFrame);
 
   nsFrameList textList(textFrame, textFrame);

layout/forms/nsFileControlFrame.cpp

@@ -71,20 +71,15 @@ nsFileControlFrame::nsFileControlFrame(nsStyleContext* aContext):
 }
 
 
-NS_IMETHODIMP
+void
 nsFileControlFrame::Init(nsIContent* aContent,
                          nsIFrame*   aParent,
                          nsIFrame*   aPrevInFlow)
 {
-  nsresult rv = nsBlockFrame::Init(aContent, aParent, aPrevInFlow);
+  nsBlockFrame::Init(aContent, aParent, aPrevInFlow);
-  NS_ENSURE_SUCCESS(rv, rv);
 
   mMouseListener = new BrowseMouseListener(this);
-  NS_ENSURE_TRUE(mMouseListener, NS_ERROR_OUT_OF_MEMORY);
   mCaptureMouseListener = new CaptureMouseListener(this);
-  NS_ENSURE_TRUE(mCaptureMouseListener, NS_ERROR_OUT_OF_MEMORY);
-
-  return rv;
 }
 
 void

layout/forms/nsFileControlFrame.h

@@ -24,9 +24,9 @@ class nsFileControlFrame : public nsBlockFrame,
 public:
   nsFileControlFrame(nsStyleContext* aContext);
 
-  NS_IMETHOD Init(nsIContent* aContent,
+  virtual void Init(nsIContent* aContent,
-                  nsIFrame*   aParent,
+                    nsIFrame*   aParent,
-                  nsIFrame*   aPrevInFlow);
+                    nsIFrame*   aPrevInFlow) MOZ_OVERRIDE;
 
   virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                                 const nsRect&           aDirtyRect,

layout/forms/nsHTMLButtonControlFrame.cpp

@@ -58,17 +58,14 @@ nsHTMLButtonControlFrame::DestroyFrom(nsIFrame* aDestructRoot)
   nsContainerFrame::DestroyFrom(aDestructRoot);
 }
 
-NS_IMETHODIMP
+void
 nsHTMLButtonControlFrame::Init(
               nsIContent*      aContent,
               nsIFrame*        aParent,
               nsIFrame*        aPrevInFlow)
 {
-  nsresult  rv = nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
+  nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
-  if (NS_SUCCEEDED(rv)) {
+  mRenderer.SetFrame(this, PresContext());
-    mRenderer.SetFrame(this, PresContext());
-  }
-  return rv;
 }
 
 NS_QUERYFRAME_HEAD(nsHTMLButtonControlFrame)

layout/forms/nsHTMLButtonControlFrame.h

@@ -52,9 +52,9 @@ public:
                          nsGUIEvent* aEvent,
                          nsEventStatus* aEventStatus) MOZ_OVERRIDE;
 
-  NS_IMETHOD  Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                   nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                   nsIFrame*        asPrevInFlow) MOZ_OVERRIDE;
+                    nsIFrame*        asPrevInFlow) MOZ_OVERRIDE;
 
   virtual nsStyleContext* GetAdditionalStyleContext(int32_t aIndex) const;
   virtual void SetAdditionalStyleContext(int32_t aIndex, 

layout/forms/nsImageControlFrame.cpp

@@ -41,9 +41,9 @@ public:
   ~nsImageControlFrame();
 
   virtual void DestroyFrom(nsIFrame* aDestructRoot);
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   NS_DECL_QUERYFRAME
   NS_DECL_FRAMEARENA_HELPERS
@@ -104,23 +104,20 @@ NS_NewImageControlFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 
 NS_IMPL_FRAMEARENA_HELPERS(nsImageControlFrame)
 
-NS_IMETHODIMP
+void
 nsImageControlFrame::Init(nsIContent*      aContent,
                           nsIFrame*        aParent,
                           nsIFrame*        aPrevInFlow)
 {
-  nsresult rv = nsImageControlFrameSuper::Init(aContent, aParent, aPrevInFlow);
+  nsImageControlFrameSuper::Init(aContent, aParent, aPrevInFlow);
-  NS_ENSURE_SUCCESS(rv, rv);
 
-  // nsIntPoint allocation can fail, in which case we just set the property 
-  // to null, which is safe
   if (aPrevInFlow) {
-    return NS_OK;
+    return;
   }
   
-  return  mContent->SetProperty(nsGkAtoms::imageClickedPoint,
+  mContent->SetProperty(nsGkAtoms::imageClickedPoint,
-                                 new nsIntPoint(0, 0),
+                        new nsIntPoint(0, 0),
-                                 IntPointDtorFunc);
+                        IntPointDtorFunc);
 }
 
 NS_QUERYFRAME_HEAD(nsImageControlFrame)

layout/forms/nsListControlFrame.cpp

@@ -984,23 +984,18 @@ nsListControlFrame::GetSizeAttribute(uint32_t *aSize) {
 
 
 //---------------------------------------------------------
-NS_IMETHODIMP  
+void
 nsListControlFrame::Init(nsIContent*     aContent,
                          nsIFrame*       aParent,
                          nsIFrame*       aPrevInFlow)
 {
-  nsresult result = nsHTMLScrollFrame::Init(aContent, aParent, aPrevInFlow);
+  nsHTMLScrollFrame::Init(aContent, aParent, aPrevInFlow);
-
-  // get the receiver interface from the browser button's content node
-  NS_ENSURE_STATE(mContent);
 
   // we shouldn't have to unregister this listener because when
   // our frame goes away all these content node go away as well
   // because our frame is the only one who references them.
   // we need to hook up our listeners before the editor is initialized
   mEventListener = new nsListEventListener(this);
-  if (!mEventListener) 
-    return NS_ERROR_OUT_OF_MEMORY;
 
   mContent->AddEventListener(NS_LITERAL_STRING("keypress"), mEventListener,
                              false, false);
@@ -1019,8 +1014,6 @@ nsListControlFrame::Init(nsIContent*     aContent,
   if (IsInDropDownMode()) {
     AddStateBits(NS_FRAME_IN_POPUP);
   }
-
-  return result;
 }
 
 already_AddRefed<nsIContent> 

layout/forms/nsListControlFrame.h

@@ -64,9 +64,9 @@ public:
                     const nsHTMLReflowState& aReflowState,
                     nsReflowStatus&          aStatus) MOZ_OVERRIDE;
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                   nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                   nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   NS_IMETHOD DidReflow(nsPresContext*           aPresContext, 
                        const nsHTMLReflowState*  aReflowState, 

layout/generic/nsBlockFrame.cpp

@@ -6455,7 +6455,7 @@ nsBlockFrame::ChildIsDirty(nsIFrame* aChild)
   nsBlockFrameSuper::ChildIsDirty(aChild);
 }
 
-NS_IMETHODIMP
+void
 nsBlockFrame::Init(nsIContent*      aContent,
                    nsIFrame*        aParent,
                    nsIFrame*        aPrevInFlow)
@@ -6466,7 +6466,7 @@ nsBlockFrame::Init(nsIContent*      aContent,
              (NS_BLOCK_FLAGS_MASK & ~NS_BLOCK_FLAGS_NON_INHERITED_MASK));
   }
 
-  nsresult rv = nsBlockFrameSuper::Init(aContent, aParent, aPrevInFlow);
+  nsBlockFrameSuper::Init(aContent, aParent, aPrevInFlow);
 
   if (!aPrevInFlow ||
       aPrevInFlow->GetStateBits() & NS_BLOCK_NEEDS_BIDI_RESOLUTION)
@@ -6477,8 +6477,6 @@ nsBlockFrame::Init(nsIContent*      aContent,
       (NS_FRAME_FONT_INFLATION_CONTAINER | NS_BLOCK_FLOAT_MGR)) {
     AddStateBits(NS_FRAME_FONT_INFLATION_FLOW_ROOT);
   }
-
-  return rv;
 }
 
 NS_IMETHODIMP

layout/generic/nsBlockFrame.h

@@ -135,9 +135,9 @@ public:
   NS_DECL_QUERYFRAME
 
   // nsIFrame
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
   NS_IMETHOD SetInitialChildList(ChildListID     aListID,
                                  nsFrameList&    aChildList);
   NS_IMETHOD  AppendFrames(ChildListID     aListID,

layout/generic/nsContainerFrame.cpp

@@ -59,12 +59,12 @@ NS_QUERYFRAME_HEAD(nsContainerFrame)
   NS_QUERYFRAME_ENTRY(nsContainerFrame)
 NS_QUERYFRAME_TAIL_INHERITING(nsSplittableFrame)
 
-NS_IMETHODIMP
+void
 nsContainerFrame::Init(nsIContent* aContent,
                        nsIFrame*   aParent,
                        nsIFrame*   aPrevInFlow)
 {
-  nsresult rv = nsSplittableFrame::Init(aContent, aParent, aPrevInFlow);
+  nsSplittableFrame::Init(aContent, aParent, aPrevInFlow);
   if (aPrevInFlow) {
     // Make sure we copy bits from our prev-in-flow that will affect
     // us. A continuation for a container frame needs to know if it
@@ -72,7 +72,6 @@ nsContainerFrame::Init(nsIContent* aContent,
     if (aPrevInFlow->GetStateBits() & NS_FRAME_HAS_CHILD_WITH_VIEW)
       AddStateBits(NS_FRAME_HAS_CHILD_WITH_VIEW);
   }
-  return rv;
 }
 
 NS_IMETHODIMP

layout/generic/nsContainerFrame.h

@@ -53,9 +53,9 @@ public:
   NS_DECL_QUERYFRAME
 
   // nsIFrame overrides
-  NS_IMETHOD Init(nsIContent* aContent,
+  virtual void Init(nsIContent* aContent,
-                  nsIFrame*   aParent,
+                    nsIFrame*   aParent,
-                  nsIFrame*   aPrevInFlow);
+                    nsIFrame*   aPrevInFlow) MOZ_OVERRIDE;
   NS_IMETHOD SetInitialChildList(ChildListID  aListID,
                                  nsFrameList& aChildList) MOZ_OVERRIDE;
   NS_IMETHOD AppendFrames(ChildListID  aListID,

layout/generic/nsFirstLetterFrame.cpp

@@ -54,7 +54,7 @@ nsFirstLetterFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
   BuildDisplayListForInline(aBuilder, aDirtyRect, aLists);
 }
 
-NS_IMETHODIMP
+void
 nsFirstLetterFrame::Init(nsIContent*      aContent,
                          nsIFrame*        aParent,
                          nsIFrame*        aPrevInFlow)
@@ -73,7 +73,7 @@ nsFirstLetterFrame::Init(nsIContent*      aContent,
     }
   }
 
-  return nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
+  nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
 }
 
 NS_IMETHODIMP

layout/generic/nsFirstLetterFrame.h

@@ -23,9 +23,9 @@ public:
                                 const nsRect&           aDirtyRect,
                                 const nsDisplayListSet& aLists) MOZ_OVERRIDE;
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
   NS_IMETHOD SetInitialChildList(ChildListID     aListID,
                                  nsFrameList&    aChildList) MOZ_OVERRIDE;
 #ifdef DEBUG

layout/generic/nsFrame.cpp

@@ -492,7 +492,7 @@ IsFontSizeInflationContainer(nsIFrame* aFrame,
   return !isInline;
 }
 
-NS_IMETHODIMP
+void
 nsFrame::Init(nsIContent*      aContent,
               nsIFrame*        aParent,
               nsIFrame*        aPrevInFlow)
@@ -560,8 +560,6 @@ nsFrame::Init(nsIContent*      aContent,
 
   if (IsBoxWrapped())
     InitBoxMetrics(false);
-
-  return NS_OK;
 }
 
 NS_IMETHODIMP nsFrame::SetInitialChildList(ChildListID     aListID,

layout/generic/nsFrame.h

@@ -142,9 +142,9 @@ public:
   NS_DECL_FRAMEARENA_HELPERS
 
   // nsIFrame
-  NS_IMETHOD  Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                   nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                   nsIFrame*        asPrevInFlow);
+                    nsIFrame*        asPrevInFlow) MOZ_OVERRIDE;
   NS_IMETHOD  SetInitialChildList(ChildListID        aListID,
                                   nsFrameList&       aChildList);
   NS_IMETHOD  AppendFrames(ChildListID     aListID,

layout/generic/nsFrameSetFrame.cpp

@@ -249,14 +249,13 @@ nsHTMLFramesetFrame::FrameResizePrefCallback(const char* aPref, void* aClosure)
   return 0;
 }
 
-NS_IMETHODIMP
+void
 nsHTMLFramesetFrame::Init(nsIContent*      aContent,
                           nsIFrame*        aParent,
                           nsIFrame*        aPrevInFlow)
 {
   nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
   // find the highest ancestor that is a frameset
-  nsresult rv = NS_OK;
   nsIFrame* parentFrame = GetParent();
   mTopLevelFrameset = this;
   while (parentFrame) {
@@ -281,17 +280,15 @@ nsHTMLFramesetFrame::Init(nsIContent*      aContent,
   NS_ASSERTION(ourContent, "Someone gave us a broken frameset element!");
   const nsFramesetSpec* rowSpecs = nullptr;
   const nsFramesetSpec* colSpecs = nullptr;
-  nsresult result = ourContent->GetRowSpec(&mNumRows, &rowSpecs);
+  // GetRowSpec and GetColSpec can fail, but when they do they set
-  NS_ENSURE_SUCCESS(result, result);
+  // mNumRows and mNumCols respectively to 0, so we deal with it fine.
-  result = ourContent->GetColSpec(&mNumCols, &colSpecs);
+  ourContent->GetRowSpec(&mNumRows, &rowSpecs);
-  NS_ENSURE_SUCCESS(result, result);
+  ourContent->GetColSpec(&mNumCols, &colSpecs);
 
   // Maximum value of mNumRows and mNumCols is NS_MAX_FRAMESET_SPEC_COUNT
   PR_STATIC_ASSERT(NS_MAX_FRAMESET_SPEC_COUNT < UINT_MAX / sizeof(nscoord));
   mRowSizes  = new nscoord[mNumRows];
   mColSizes  = new nscoord[mNumCols];
-  if (!mRowSizes || !mColSizes)
-    return NS_ERROR_OUT_OF_MEMORY;
 
   // Ensure we can't overflow numCells
   PR_STATIC_ASSERT(NS_MAX_FRAMESET_SPEC_COUNT < INT32_MAX / NS_MAX_FRAMESET_SPEC_COUNT);
@@ -299,15 +296,11 @@ nsHTMLFramesetFrame::Init(nsIContent*      aContent,
 
   PR_STATIC_ASSERT(NS_MAX_FRAMESET_SPEC_COUNT < UINT_MAX / sizeof(nsHTMLFramesetBorderFrame*));
   mVerBorders    = new nsHTMLFramesetBorderFrame*[mNumCols];  // 1 more than number of ver borders
-  if (!mVerBorders)
-    return NS_ERROR_OUT_OF_MEMORY;
 
   for (int verX  = 0; verX < mNumCols; verX++)
     mVerBorders[verX]    = nullptr;
 
   mHorBorders    = new nsHTMLFramesetBorderFrame*[mNumRows];  // 1 more than number of hor borders
-  if (!mHorBorders)
-    return NS_ERROR_OUT_OF_MEMORY;
 
   for (int horX = 0; horX < mNumRows; horX++)
     mHorBorders[horX]    = nullptr;
@@ -320,8 +313,6 @@ nsHTMLFramesetFrame::Init(nsIContent*      aContent,
                    < UINT_MAX / sizeof(nsBorderColor) / NS_MAX_FRAMESET_SPEC_COUNT);
   mChildFrameborder  = new nsFrameborder[numCells];
   mChildBorderColors  = new nsBorderColor[numCells];
-  if (!mChildFrameborder || !mChildBorderColors)
-    return NS_ERROR_OUT_OF_MEMORY;
 
   // create the children frames; skip content which isn't <frameset> or <frame>
   mChildCount = 0; // number of <frame> or <frameset> children
@@ -359,45 +350,29 @@ nsHTMLFramesetFrame::Init(nsIContent*      aContent,
     nsIAtom *tag = child->Tag();
     if (tag == nsGkAtoms::frameset || tag == nsGkAtoms::frame) {
       nsRefPtr<nsStyleContext> kidSC;
-      nsresult result;
 
       kidSC = shell->StyleSet()->ResolveStyleFor(child->AsElement(),
                                                  mStyleContext);
       if (tag == nsGkAtoms::frameset) {
         frame = NS_NewHTMLFramesetFrame(shell, kidSC);
-        if (MOZ_UNLIKELY(!frame))
-          return NS_ERROR_OUT_OF_MEMORY;
 
         nsHTMLFramesetFrame* childFrame = (nsHTMLFramesetFrame*)frame;
         childFrame->SetParentFrameborder(frameborder);
         childFrame->SetParentBorderWidth(borderWidth);
         childFrame->SetParentBorderColor(borderColor);
-        result = frame->Init(child, this, nullptr);
+        frame->Init(child, this, nullptr);
-        if (NS_FAILED(result)) {
-          frame->Destroy();
-          return result;
-        }
 
         mChildBorderColors[mChildCount].Set(childFrame->GetBorderColor());
       } else { // frame
         frame = NS_NewSubDocumentFrame(shell, kidSC);
-        if (MOZ_UNLIKELY(!frame))
-          return NS_ERROR_OUT_OF_MEMORY;
 
-        result = frame->Init(child, this, nullptr);
+        frame->Init(child, this, nullptr);
-        if (NS_FAILED(result)) {
-          frame->Destroy();
-          return result;
-        }
 
         mChildFrameborder[mChildCount] = GetFrameBorder(child);
         mChildBorderColors[mChildCount].Set(GetBorderColor(child));
       }
       child->SetPrimaryFrame(frame);
 
-      if (NS_FAILED(result))
-        return result;
-
       mFrames.AppendFrame(nullptr, frame);
 
       mChildCount++;
@@ -410,19 +385,12 @@ nsHTMLFramesetFrame::Init(nsIContent*      aContent,
     nsRefPtr<nsStyleContext> pseudoStyleContext;
     pseudoStyleContext = shell->StyleSet()->
       ResolveAnonymousBoxStyle(nsCSSAnonBoxes::framesetBlank, mStyleContext);
-    if (!pseudoStyleContext) {
-      return NS_ERROR_OUT_OF_MEMORY;
-    }
 
     // XXX the blank frame is using the content of its parent - at some point it
     // should just have null content, if we support that
     nsHTMLFramesetBlankFrame* blankFrame = new (shell) nsHTMLFramesetBlankFrame(pseudoStyleContext);
 
-    result = blankFrame->Init(mContent, this, nullptr);
+    blankFrame->Init(mContent, this, nullptr);
-    if (NS_FAILED(result)) {
-      blankFrame->Destroy();
-      return result;
-    }
 
     mFrames.AppendFrame(nullptr, blankFrame);
 
@@ -431,7 +399,6 @@ nsHTMLFramesetFrame::Init(nsIContent*      aContent,
   }
 
   mNonBorderChildCount = mChildCount;
-  return rv;
 }
 
 NS_IMETHODIMP

layout/generic/nsFrameSetFrame.h

@@ -78,9 +78,9 @@ public:
 
   virtual ~nsHTMLFramesetFrame();
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   NS_IMETHOD SetInitialChildList(ChildListID  aListID,
                                  nsFrameList& aChildList);

layout/generic/nsHTMLCanvasFrame.cpp

@@ -90,19 +90,17 @@ NS_NewHTMLCanvasFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 
 NS_IMPL_FRAMEARENA_HELPERS(nsHTMLCanvasFrame)
 
-NS_IMETHODIMP
+void
 nsHTMLCanvasFrame::Init(nsIContent* aContent,
                         nsIFrame*   aParent,
                         nsIFrame*   aPrevInFlow)
 {
-  nsresult rv = nsSplittableFrame::Init(aContent, aParent, aPrevInFlow);
+  nsSplittableFrame::Init(aContent, aParent, aPrevInFlow);
 
   // We can fill in the canvas before the canvas frame is created, in
   // which case we never get around to marking the layer active. Therefore,
   // we mark it active here when we create the frame.
   MarkLayersActive(nsChangeHint(0));
-
-  return rv;
 }
 
 nsHTMLCanvasFrame::~nsHTMLCanvasFrame()

layout/generic/nsHTMLCanvasFrame.h

@@ -38,9 +38,9 @@ public:
 
   nsHTMLCanvasFrame(nsStyleContext* aContext) : nsContainerFrame(aContext) {}
 
-  NS_IMETHOD Init(nsIContent* aContent,
+  virtual void Init(nsIContent* aContent,
-                  nsIFrame*   aParent,
+                    nsIFrame*   aParent,
-                  nsIFrame*   aPrevInFlow) MOZ_OVERRIDE;
+                    nsIFrame*   aPrevInFlow) MOZ_OVERRIDE;
 
   virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                                 const nsRect&           aDirtyRect,

layout/generic/nsIFrame.h

@@ -577,17 +577,15 @@ public:
    * frame (the frame that was split).
    *
    * If you want a view associated with your frame, you should create the view
-   * now.
+   * after Init() has returned.
    *
    * @param   aContent the content object associated with the frame
-   * @param   aGeometricParent  the geometric parent frame
+   * @param   aParent the parent frame
-   * @param   aContentParent  the content parent frame
-   * @param   aContext the style context associated with the frame
    * @param   aPrevInFlow the prev-in-flow frame
    */
-  NS_IMETHOD  Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                   nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                   nsIFrame*        aPrevInFlow) = 0;
+                    nsIFrame*        aPrevInFlow) = 0;
 
   /**
    * Destroys this frame and each of its child frames (recursively calls

layout/generic/nsImageFrame.cpp

@@ -226,18 +226,19 @@ nsImageFrame::DestroyFrom(nsIFrame* aDestructRoot)
 
 
 
-NS_IMETHODIMP
+void
 nsImageFrame::Init(nsIContent*      aContent,
                    nsIFrame*        aParent,
                    nsIFrame*        aPrevInFlow)
 {
-  nsresult rv = nsSplittableFrame::Init(aContent, aParent, aPrevInFlow);
+  nsSplittableFrame::Init(aContent, aParent, aPrevInFlow);
-  NS_ENSURE_SUCCESS(rv, rv);
 
   mListener = new nsImageListener(this);
 
   nsCOMPtr<nsIImageLoadingContent> imageLoader = do_QueryInterface(aContent);
-  NS_ENSURE_TRUE(imageLoader, NS_ERROR_UNEXPECTED);
+  if (!imageLoader) {
+    NS_RUNTIMEABORT("Why do we have an nsImageFrame here at all?");
+  }
 
   {
     // Push a null JSContext on the stack so that code that runs
@@ -275,8 +276,6 @@ nsImageFrame::Init(nsIContent*      aContent,
       image->SetAnimationMode(aPresContext->ImageAnimationMode());
     }
   }
-
-  return rv;
 }
 
 bool

layout/generic/nsImageFrame.h

@@ -74,9 +74,9 @@ public:
   NS_DECL_QUERYFRAME
 
   virtual void DestroyFrom(nsIFrame* aDestructRoot);
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
   virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                                 const nsRect&           aDirtyRect,
                                 const nsDisplayListSet& aLists) MOZ_OVERRIDE;

layout/generic/nsObjectFrame.cpp

@@ -288,7 +288,7 @@ NS_IMETHODIMP nsObjectFrame::GetPluginPort(HWND *aPort)
 #endif
 #endif
 
-NS_IMETHODIMP 
+void
 nsObjectFrame::Init(nsIContent*      aContent,
                     nsIFrame*        aParent,
                     nsIFrame*        aPrevInFlow)
@@ -296,9 +296,7 @@ nsObjectFrame::Init(nsIContent*      aContent,
   PR_LOG(GetObjectFrameLog(), PR_LOG_DEBUG,
          ("Initializing nsObjectFrame %p for content %p\n", this, aContent));
 
-  nsresult rv = nsObjectFrameSuper::Init(aContent, aParent, aPrevInFlow);
+  nsObjectFrameSuper::Init(aContent, aParent, aPrevInFlow);
-
-  return rv;
 }
 
 void

layout/generic/nsObjectFrame.h

@@ -50,9 +50,9 @@ public:
   NS_DECL_QUERYFRAME
   NS_DECL_QUERYFRAME_TARGET(nsObjectFrame)
 
-  NS_IMETHOD Init(nsIContent* aContent,
+  virtual void Init(nsIContent* aContent,
-                  nsIFrame* aParent,
+                    nsIFrame* aParent,
-                  nsIFrame* aPrevInFlow);
+                    nsIFrame* aPrevInFlow) MOZ_OVERRIDE;
   virtual nscoord GetMinWidth(nsRenderingContext *aRenderingContext);
   virtual nscoord GetPrefWidth(nsRenderingContext *aRenderingContext);
   NS_IMETHOD Reflow(nsPresContext* aPresContext,

layout/generic/nsSplittableFrame.cpp

@@ -15,20 +15,18 @@
 
 NS_IMPL_FRAMEARENA_HELPERS(nsSplittableFrame)
 
-NS_IMETHODIMP
+void
 nsSplittableFrame::Init(nsIContent*      aContent,
                         nsIFrame*        aParent,
                         nsIFrame*        aPrevInFlow)
 {
-  nsresult rv = nsFrame::Init(aContent, aParent, aPrevInFlow);
+  nsFrame::Init(aContent, aParent, aPrevInFlow);
 
   if (aPrevInFlow) {
     // Hook the frame into the flow
     SetPrevInFlow(aPrevInFlow);
     aPrevInFlow->SetNextInFlow(this);
   }
-
-  return rv;
 }
 
 void

layout/generic/nsSplittableFrame.h

@@ -20,9 +20,9 @@ class nsSplittableFrame : public nsFrame
 public:
   NS_DECL_FRAMEARENA_HELPERS
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
   
   virtual nsSplittableType GetSplittableType() const;
 

layout/generic/nsSubDocumentFrame.cpp

@@ -114,7 +114,7 @@ InsertViewsInReverseOrder(nsView* aSibling, nsView* aParent);
 static void
 EndSwapDocShellsForViews(nsView* aView);
 
-NS_IMETHODIMP
+void
 nsSubDocumentFrame::Init(nsIContent*     aContent,
                          nsIFrame*       aParent,
                          nsIFrame*       aPrevInFlow)
@@ -125,9 +125,7 @@ nsSubDocumentFrame::Init(nsIContent*     aContent,
     mIsInline = frameElem ? false : true;
   }
 
-  nsresult rv =  nsLeafFrame::Init(aContent, aParent, aPrevInFlow);
+  nsLeafFrame::Init(aContent, aParent, aPrevInFlow);
-  if (NS_FAILED(rv))
-    return rv;
 
   // We are going to create an inner view.  If we need a view for the
   // OuterFrame but we wait for the normal view creation path in
@@ -169,7 +167,6 @@ nsSubDocumentFrame::Init(nsIContent*     aContent,
   }
 
   nsContentUtils::AddScriptRunner(new AsyncFrameInit(this));
-  return NS_OK;
 }
 
 inline int32_t ConvertOverflow(uint8_t aOverflow)

layout/generic/nsSubDocumentFrame.h

@@ -39,9 +39,9 @@ public:
       ~(nsIFrame::eReplaced | nsIFrame::eReplacedContainsBlock));
   }
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   virtual void DestroyFrom(nsIFrame* aDestructRoot);
 

layout/generic/nsTextFrame.h

@@ -55,9 +55,9 @@ public:
                                 const nsRect&           aDirtyRect,
                                 const nsDisplayListSet& aLists) MOZ_OVERRIDE;
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   virtual void DestroyFrom(nsIFrame* aDestructRoot);
   

layout/generic/nsTextFrameThebes.cpp

@@ -3912,7 +3912,7 @@ nsTextFrame::AccessibleType()
 
 
 //-----------------------------------------------------------------------------
-NS_IMETHODIMP
+void
 nsTextFrame::Init(nsIContent*      aContent,
                   nsIFrame*        aParent,
                   nsIFrame*        aPrevInFlow)
@@ -3933,7 +3933,7 @@ nsTextFrame::Init(nsIContent*      aContent,
 
   // We're not a continuing frame.
   // mContentOffset = 0; not necessary since we get zeroed out at init
-  return nsFrame::Init(aContent, aParent, aPrevInFlow);
+  nsFrame::Init(aContent, aParent, aPrevInFlow);
 }
 
 void
@@ -3975,9 +3975,9 @@ public:
 
   friend nsIFrame* NS_NewContinuingTextFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   virtual void DestroyFrom(nsIFrame* aDestructRoot);
 
@@ -4026,14 +4026,14 @@ protected:
   nsIFrame* mPrevContinuation;
 };
 
-NS_IMETHODIMP
+void
 nsContinuingTextFrame::Init(nsIContent* aContent,
                             nsIFrame*   aParent,
                             nsIFrame*   aPrevInFlow)
 {
   NS_ASSERTION(aPrevInFlow, "Must be a continuation!");
   // NOTE: bypassing nsTextFrame::Init!!!
-  nsresult rv = nsFrame::Init(aContent, aParent, aPrevInFlow);
+  nsFrame::Init(aContent, aParent, aPrevInFlow);
 
 #ifdef IBMBIDI
   nsTextFrame* nextContinuation =
@@ -4092,8 +4092,6 @@ nsContinuingTextFrame::Init(nsIContent* aContent,
     mState |= NS_FRAME_IS_BIDI;
   } // prev frame is bidi
 #endif // IBMBIDI
-
-  return rv;
 }
 
 void

layout/generic/nsViewportFrame.cpp

@@ -29,12 +29,12 @@ NS_NewViewportFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 
 NS_IMPL_FRAMEARENA_HELPERS(ViewportFrame)
 
-NS_IMETHODIMP
+void
 ViewportFrame::Init(nsIContent*      aContent,
                     nsIFrame*        aParent,
                     nsIFrame*        aPrevInFlow)
 {
-  nsresult rv = Super::Init(aContent, aParent, aPrevInFlow);
+  Super::Init(aContent, aParent, aPrevInFlow);
 
   nsIFrame* parent = nsLayoutUtils::GetCrossDocParentFrame(this);
   if (parent) {
@@ -42,8 +42,6 @@ ViewportFrame::Init(nsIContent*      aContent,
 
     mState |= state & (NS_FRAME_IN_POPUP);
   }
-
-  return rv;
 }
 
 NS_IMETHODIMP

layout/generic/nsViewportFrame.h

@@ -33,9 +33,9 @@ public:
   {}
   virtual ~ViewportFrame() { } // useful for debugging
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        asPrevInFlow) MOZ_OVERRIDE;
+                    nsIFrame*        asPrevInFlow) MOZ_OVERRIDE;
 
   NS_IMETHOD SetInitialChildList(ChildListID     aListID,
                                  nsFrameList&    aChildList) MOZ_OVERRIDE;

layout/mathml/nsMathMLmactionFrame.cpp

@@ -91,7 +91,7 @@ nsMathMLmactionFrame::~nsMathMLmactionFrame()
   }
 }
 
-NS_IMETHODIMP
+void
 nsMathMLmactionFrame::Init(nsIContent*      aContent,
                            nsIFrame*        aParent,
                            nsIFrame*        aPrevInFlow)
@@ -104,7 +104,7 @@ nsMathMLmactionFrame::Init(nsIContent*      aContent,
   mActionType = GetActionType(aContent);
 
   // Let the base class do the rest
-  return nsMathMLContainerFrame::Init(aContent, aParent, aPrevInFlow);
+  nsMathMLContainerFrame::Init(aContent, aParent, aPrevInFlow);
 }
 
 NS_IMETHODIMP

layout/mathml/nsMathMLmactionFrame.h

@@ -24,10 +24,10 @@ public:
   NS_IMETHOD
   TransmitAutomaticData();
 
-  NS_IMETHOD
+  virtual void
   Init(nsIContent*      aContent,
        nsIFrame*        aParent,
-       nsIFrame*        aPrevInFlow);
+       nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   NS_IMETHOD
   SetInitialChildList(ChildListID     aListID,

layout/mathml/nsMathMLmrootFrame.cpp

@@ -51,12 +51,12 @@ nsMathMLmrootFrame::~nsMathMLmrootFrame()
 {
 }
 
-NS_IMETHODIMP
+void
 nsMathMLmrootFrame::Init(nsIContent*      aContent,
                          nsIFrame*        aParent,
                          nsIFrame*        aPrevInFlow)
 {
-  nsresult rv = nsMathMLContainerFrame::Init(aContent, aParent, aPrevInFlow);
+  nsMathMLContainerFrame::Init(aContent, aParent, aPrevInFlow);
   
   nsPresContext *presContext = PresContext();
 
@@ -66,8 +66,6 @@ nsMathMLmrootFrame::Init(nsIContent*      aContent,
   nsAutoString sqrChar; sqrChar.Assign(kSqrChar);
   mSqrChar.SetData(presContext, sqrChar);
   ResolveMathMLCharStyle(presContext, mContent, mStyleContext, &mSqrChar, true);
-
-  return rv;
 }
 
 NS_IMETHODIMP

layout/mathml/nsMathMLmrootFrame.h

@@ -26,10 +26,10 @@ public:
   virtual nsStyleContext*
   GetAdditionalStyleContext(int32_t aIndex) const;
 
-  NS_IMETHOD
+  virtual void
   Init(nsIContent*      aContent,
        nsIFrame*        aParent,
-       nsIFrame*        aPrevInFlow);
+       nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   NS_IMETHOD
   TransmitAutomaticData() MOZ_OVERRIDE;

layout/mathml/nsMathMLmsqrtFrame.cpp

@@ -35,16 +35,14 @@ nsMathMLmsqrtFrame::~nsMathMLmsqrtFrame()
 {
 }
 
-NS_IMETHODIMP
+void
 nsMathMLmsqrtFrame::Init(nsIContent*      aContent,
                          nsIFrame*        aParent,
                          nsIFrame*        aPrevInFlow)
 {
-  nsresult rv = nsMathMLContainerFrame::Init(aContent, aParent, aPrevInFlow);
+  nsMathMLContainerFrame::Init(aContent, aParent, aPrevInFlow);
   AllocateMathMLChar(NOTATION_RADICAL);
   mNotationsToDraw |= NOTATION_RADICAL;
-
-  return rv;
 }
 
 NS_IMETHODIMP

layout/mathml/nsMathMLmsqrtFrame.h

@@ -39,10 +39,10 @@ public:
   friend nsIFrame* NS_NewMathMLmsqrtFrame(nsIPresShell*   aPresShell,
                                           nsStyleContext* aContext);
 
-  NS_IMETHOD
+  virtual void
   Init(nsIContent* aContent,
        nsIFrame*   aParent,
-       nsIFrame*   aPrevInFlow);
+       nsIFrame*   aPrevInFlow) MOZ_OVERRIDE;
 
   NS_IMETHOD
   InheritAutomaticData(nsIFrame* aParent) MOZ_OVERRIDE;

layout/svg/SVGFEContainerFrame.cpp

@@ -47,9 +47,9 @@ public:
   virtual void DidSetStyleContext(nsStyleContext* aOldStyleContext);
 
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent* aContent,
+  virtual void Init(nsIContent* aContent,
-                  nsIFrame*   aParent,
+                    nsIFrame*   aParent,
-                  nsIFrame*   aPrevInFlow);
+                    nsIFrame*   aPrevInFlow) MOZ_OVERRIDE;
 #endif
   /**
    * Get the "type" of the frame
@@ -84,7 +84,7 @@ SVGFEContainerFrame::DidSetStyleContext(nsStyleContext* aOldStyleContext)
 }
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 SVGFEContainerFrame::Init(nsIContent* aContent,
                           nsIFrame* aParent,
                           nsIFrame* aPrevInFlow)
@@ -93,7 +93,7 @@ SVGFEContainerFrame::Init(nsIContent* aContent,
                "Trying to construct an SVGFEContainerFrame for a "
                "content element that doesn't support the right interfaces");
 
-  return SVGFEContainerFrameBase::Init(aContent, aParent, aPrevInFlow);
+  SVGFEContainerFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/SVGFEImageFrame.cpp

@@ -31,9 +31,9 @@ protected:
 public:
   NS_DECL_FRAMEARENA_HELPERS
 
-  NS_IMETHOD Init(nsIContent* aContent,
+  virtual void Init(nsIContent* aContent,
-                  nsIFrame*   aParent,
+                    nsIFrame*   aParent,
-                  nsIFrame*   aPrevInFlow);
+                    nsIFrame*   aPrevInFlow) MOZ_OVERRIDE;
   virtual void DestroyFrom(nsIFrame* aDestructRoot);
 
   virtual bool IsFrameOfType(uint32_t aFlags) const
@@ -96,7 +96,7 @@ SVGFEImageFrame::DestroyFrom(nsIFrame* aDestructRoot)
   SVGFEImageFrameBase::DestroyFrom(aDestructRoot);
 }
 
-NS_IMETHODIMP
+void
 SVGFEImageFrame::Init(nsIContent* aContent,
                         nsIFrame* aParent,
                         nsIFrame* aPrevInFlow)
@@ -114,8 +114,6 @@ SVGFEImageFrame::Init(nsIContent* aContent,
     // We assume that feImage's are always visible.
     imageLoader->IncrementVisibleCount();
   }
-
-  return NS_OK;
 }
 
 nsIAtom *

layout/svg/SVGFELeafFrame.cpp

@@ -30,9 +30,9 @@ public:
   NS_DECL_FRAMEARENA_HELPERS
 
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent* aContent,
+  virtual void Init(nsIContent* aContent,
-                  nsIFrame*   aParent,
+                    nsIFrame*   aParent,
-                  nsIFrame*   aPrevInFlow);
+                    nsIFrame*   aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   virtual bool IsFrameOfType(uint32_t aFlags) const
@@ -82,7 +82,7 @@ SVGFELeafFrame::DidSetStyleContext(nsStyleContext* aOldStyleContext)
 }
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 SVGFELeafFrame::Init(nsIContent* aContent,
                      nsIFrame* aParent,
                      nsIFrame* aPrevInFlow)
@@ -91,7 +91,7 @@ SVGFELeafFrame::Init(nsIContent* aContent,
                "Trying to construct an SVGFELeafFrame for a "
                "content element that doesn't support the right interfaces");
 
-  return SVGFELeafFrameBase::Init(aContent, aParent, aPrevInFlow);
+  SVGFELeafFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/SVGViewFrame.cpp

@@ -35,9 +35,9 @@ public:
   NS_DECL_FRAMEARENA_HELPERS
 
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent* aContent,
+  virtual void Init(nsIContent* aContent,
-                  nsIFrame*   aParent,
+                    nsIFrame*   aParent,
-                  nsIFrame*   aPrevInFlow);
+                    nsIFrame*   aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   virtual bool IsFrameOfType(uint32_t aFlags) const
@@ -78,7 +78,7 @@ NS_NewSVGViewFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 NS_IMPL_FRAMEARENA_HELPERS(SVGViewFrame)
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 SVGViewFrame::Init(nsIContent* aContent,
                    nsIFrame* aParent,
                    nsIFrame* aPrevInFlow)
@@ -86,7 +86,7 @@ SVGViewFrame::Init(nsIContent* aContent,
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::view),
                "Content is not an SVG view");
 
-  return SVGViewFrameBase::Init(aContent, aParent, aPrevInFlow);
+  SVGViewFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGAFrame.cpp

@@ -32,9 +32,9 @@ public:
   NS_DECL_FRAMEARENA_HELPERS
 
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   // nsIFrame:
@@ -86,7 +86,7 @@ NS_IMPL_FRAMEARENA_HELPERS(nsSVGAFrame)
 //----------------------------------------------------------------------
 // nsIFrame methods
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGAFrame::Init(nsIContent* aContent,
                   nsIFrame* aParent,
                   nsIFrame* aPrevInFlow)
@@ -95,7 +95,7 @@ nsSVGAFrame::Init(nsIContent* aContent,
                "Trying to construct an SVGAFrame for a "
                "content element that doesn't support the right interfaces");
 
-  return nsSVGAFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGAFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGClipPathFrame.cpp

@@ -296,7 +296,7 @@ nsSVGClipPathFrame::AttributeChanged(int32_t         aNameSpaceID,
                                                   aAttribute, aModType);
 }
 
-NS_IMETHODIMP
+void
 nsSVGClipPathFrame::Init(nsIContent* aContent,
                          nsIFrame* aParent,
                          nsIFrame* aPrevInFlow)
@@ -305,7 +305,7 @@ nsSVGClipPathFrame::Init(nsIContent* aContent,
                "Content is not an SVG clipPath!");
 
   AddStateBits(NS_STATE_SVG_CLIPPATH_CHILD);
-  return nsSVGClipPathFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGClipPathFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 
 nsIAtom *

layout/svg/nsSVGClipPathFrame.h

@@ -56,9 +56,9 @@ public:
                               nsIAtom*        aAttribute,
                               int32_t         aModType);
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   /**
    * Get the "type" of the frame

layout/svg/nsSVGContainerFrame.cpp

@@ -80,7 +80,7 @@ nsSVGContainerFrame::UpdateOverflow()
   return nsSVGContainerFrameBase::UpdateOverflow();
 }
 
-NS_IMETHODIMP
+void
 nsSVGDisplayContainerFrame::Init(nsIContent* aContent,
                                  nsIFrame* aParent,
                                  nsIFrame* aPrevInFlow)
@@ -89,8 +89,7 @@ nsSVGDisplayContainerFrame::Init(nsIContent* aContent,
     AddStateBits(aParent->GetStateBits() &
       (NS_STATE_SVG_NONDISPLAY_CHILD | NS_STATE_SVG_CLIPPATH_CHILD));
   }
-  nsresult rv = nsSVGContainerFrame::Init(aContent, aParent, aPrevInFlow);
+  nsSVGContainerFrame::Init(aContent, aParent, aPrevInFlow);
-  return rv;
 }
 
 void

layout/svg/nsSVGContainerFrame.h

@@ -125,9 +125,9 @@ public:
                           nsFrameList&    aFrameList) MOZ_OVERRIDE;
   NS_IMETHOD RemoveFrame(ChildListID     aListID,
                          nsIFrame*       aOldFrame) MOZ_OVERRIDE;
-  NS_IMETHOD Init(nsIContent*      aContent,
+ virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                   nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
+                   nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                                 const nsRect&           aDirtyRect,

layout/svg/nsSVGFilterFrame.cpp

@@ -528,7 +528,7 @@ nsSVGFilterFrame::GetPostFilterBounds(nsIFrame *aFilteredFrame,
 }
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGFilterFrame::Init(nsIContent* aContent,
                        nsIFrame* aParent,
                        nsIFrame* aPrevInFlow)
@@ -536,7 +536,7 @@ nsSVGFilterFrame::Init(nsIContent* aContent,
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::filter),
                "Content is not an SVG filter");
 
-  return nsSVGFilterFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGFilterFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGFilterFrame.h

@@ -97,9 +97,9 @@ public:
                              const nsRect *aPreFilterBounds = nullptr);
 
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   /**

layout/svg/nsSVGForeignObjectFrame.cpp

@@ -52,7 +52,7 @@ NS_QUERYFRAME_HEAD(nsSVGForeignObjectFrame)
   NS_QUERYFRAME_ENTRY(nsISVGChildFrame)
 NS_QUERYFRAME_TAIL_INHERITING(nsSVGForeignObjectFrameBase)
 
-NS_IMETHODIMP
+void
 nsSVGForeignObjectFrame::Init(nsIContent* aContent,
                               nsIFrame*   aParent,
                               nsIFrame*   aPrevInFlow)
@@ -60,16 +60,14 @@ nsSVGForeignObjectFrame::Init(nsIContent* aContent,
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::foreignObject),
                "Content is not an SVG foreignObject!");
 
-  nsresult rv = nsSVGForeignObjectFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGForeignObjectFrameBase::Init(aContent, aParent, aPrevInFlow);
   AddStateBits(aParent->GetStateBits() &
                (NS_STATE_SVG_NONDISPLAY_CHILD | NS_STATE_SVG_CLIPPATH_CHILD));
   AddStateBits(NS_FRAME_FONT_INFLATION_CONTAINER |
                NS_FRAME_FONT_INFLATION_FLOW_ROOT);
-  if (NS_SUCCEEDED(rv) &&
+  if (!(mState & NS_STATE_SVG_NONDISPLAY_CHILD)) {
-      !(mState & NS_STATE_SVG_NONDISPLAY_CHILD)) {
     nsSVGUtils::GetOuterSVGFrame(this)->RegisterForeignObject(this);
   }
-  return rv;
 }
 
 void nsSVGForeignObjectFrame::DestroyFrom(nsIFrame* aDestructRoot)

layout/svg/nsSVGForeignObjectFrame.h

@@ -31,9 +31,9 @@ public:
   NS_DECL_FRAMEARENA_HELPERS
 
   // nsIFrame:
-  NS_IMETHOD  Init(nsIContent* aContent,
+  virtual void Init(nsIContent* aContent,
-                   nsIFrame*   aParent,
+                    nsIFrame*   aParent,
-                   nsIFrame*   aPrevInFlow);
+                    nsIFrame*   aPrevInFlow) MOZ_OVERRIDE;
   virtual void DestroyFrom(nsIFrame* aDestructRoot);
   NS_IMETHOD  AttributeChanged(int32_t         aNameSpaceID,
                                nsIAtom*        aAttribute,

layout/svg/nsSVGGFrame.cpp

@@ -28,7 +28,7 @@ NS_NewSVGGFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 NS_IMPL_FRAMEARENA_HELPERS(nsSVGGFrame)
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGGFrame::Init(nsIContent* aContent,
                   nsIFrame* aParent,
                   nsIFrame* aPrevInFlow)
@@ -37,7 +37,7 @@ nsSVGGFrame::Init(nsIContent* aContent,
   NS_ASSERTION(transformable,
                "The element doesn't support nsIDOMSVGTransformable\n");
 
-  return nsSVGGFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGGFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGGFrame.h

@@ -23,9 +23,9 @@ public:
   NS_DECL_FRAMEARENA_HELPERS
 
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   /**

layout/svg/nsSVGGeometryFrame.cpp

@@ -19,15 +19,14 @@ NS_IMPL_FRAMEARENA_HELPERS(nsSVGGeometryFrame)
 //----------------------------------------------------------------------
 // nsIFrame methods
 
-NS_IMETHODIMP
+void
 nsSVGGeometryFrame::Init(nsIContent* aContent,
                          nsIFrame* aParent,
                          nsIFrame* aPrevInFlow)
 {
   AddStateBits(aParent->GetStateBits() &
                (NS_STATE_SVG_NONDISPLAY_CHILD | NS_STATE_SVG_CLIPPATH_CHILD));
-  nsresult rv = nsSVGGeometryFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGGeometryFrameBase::Init(aContent, aParent, aPrevInFlow);
-  return rv;
 }
 
 //----------------------------------------------------------------------

layout/svg/nsSVGGeometryFrame.h

@@ -42,9 +42,9 @@ protected:
 
 public:
   // nsIFrame interface:
-  NS_IMETHOD Init(nsIContent* aContent,
+  virtual void Init(nsIContent* aContent,
-                  nsIFrame* aParent,
+		    nsIFrame* aParent,
-                  nsIFrame* aPrevInFlow);
+		    nsIFrame* aPrevInFlow) MOZ_OVERRIDE;
 
   virtual bool IsFrameOfType(uint32_t aFlags) const
   {

layout/svg/nsSVGGlyphFrame.cpp

@@ -313,7 +313,7 @@ nsSVGGlyphFrame::DidSetStyleContext(nsStyleContext* aOldStyleContext)
   }
 }
 
-NS_IMETHODIMP
+void
 nsSVGGlyphFrame::Init(nsIContent* aContent,
                       nsIFrame* aParent,
                       nsIFrame* aPrevInFlow)
@@ -332,7 +332,7 @@ nsSVGGlyphFrame::Init(nsIContent* aContent,
                "trying to construct an SVGGlyphFrame for wrong content element");
 #endif /* DEBUG */
 
-  return nsSVGGlyphFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGGlyphFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 
 nsIAtom *

layout/svg/nsSVGGlyphFrame.h

@@ -193,9 +193,9 @@ public:
 
   virtual void DidSetStyleContext(nsStyleContext* aOldStyleContext);
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   /**
    * Get the "type" of the frame

layout/svg/nsSVGGradientFrame.cpp

@@ -420,7 +420,7 @@ nsSVGGradientFrame::GetStopFrame(int32_t aIndex, nsIFrame * *aStopFrame)
 // -------------------------------------------------------------------------
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGLinearGradientFrame::Init(nsIContent* aContent,
                                nsIFrame* aParent,
                                nsIFrame* aPrevInFlow)
@@ -428,7 +428,7 @@ nsSVGLinearGradientFrame::Init(nsIContent* aContent,
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::linearGradient),
                "Content is not an SVG linearGradient");
 
-  return nsSVGLinearGradientFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGLinearGradientFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 
@@ -533,7 +533,7 @@ nsSVGLinearGradientFrame::CreateGradient()
 // -------------------------------------------------------------------------
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGRadialGradientFrame::Init(nsIContent* aContent,
                                nsIFrame* aParent,
                                nsIFrame* aPrevInFlow)
@@ -541,7 +541,7 @@ nsSVGRadialGradientFrame::Init(nsIContent* aContent,
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::radialGradient),
                "Content is not an SVG radialGradient");
 
-  return nsSVGRadialGradientFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGRadialGradientFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGGradientFrame.h

@@ -143,9 +143,9 @@ public:
 
   // nsIFrame interface:
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   virtual nsIAtom* GetType() const;  // frame type: nsGkAtoms::svgLinearGradientFrame
@@ -188,9 +188,9 @@ public:
 
   // nsIFrame interface:
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   virtual nsIAtom* GetType() const;  // frame type: nsGkAtoms::svgRadialGradientFrame

layout/svg/nsSVGImageFrame.cpp

@@ -66,9 +66,9 @@ public:
   NS_IMETHOD  AttributeChanged(int32_t         aNameSpaceID,
                                nsIAtom*        aAttribute,
                                int32_t         aModType);
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
   virtual void DestroyFrom(nsIFrame* aDestructRoot);
 
   /**
@@ -129,7 +129,7 @@ nsSVGImageFrame::~nsSVGImageFrame()
   mListener = nullptr;
 }
 
-NS_IMETHODIMP
+void
 nsSVGImageFrame::Init(nsIContent* aContent,
                       nsIFrame* aParent,
                       nsIFrame* aPrevInFlow)
@@ -137,13 +137,13 @@ nsSVGImageFrame::Init(nsIContent* aContent,
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::image),
                "Content is not an SVG image!");
 
-  nsresult rv = nsSVGImageFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGImageFrameBase::Init(aContent, aParent, aPrevInFlow);
-  if (NS_FAILED(rv)) return rv;
 
   mListener = new nsSVGImageListener(this);
-  if (!mListener) return NS_ERROR_OUT_OF_MEMORY;
   nsCOMPtr<nsIImageLoadingContent> imageLoader = do_QueryInterface(mContent);
-  NS_ENSURE_TRUE(imageLoader, NS_ERROR_UNEXPECTED);
+  if (!imageLoader) {
+    NS_RUNTIMEABORT("Why is this not an image loading content?");
+  }
 
   // We should have a PresContext now, so let's notify our image loader that
   // we need to register any image animations with the refresh driver.
@@ -156,8 +156,6 @@ nsSVGImageFrame::Init(nsIContent* aContent,
   pusher.PushNull();
 
   imageLoader->AddObserver(mListener);
-
-  return NS_OK; 
 }
 
 /* virtual */ void

layout/svg/nsSVGInnerSVGFrame.cpp

@@ -35,7 +35,7 @@ NS_QUERYFRAME_HEAD(nsSVGInnerSVGFrame)
 NS_QUERYFRAME_TAIL_INHERITING(nsSVGInnerSVGFrameBase)
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGInnerSVGFrame::Init(nsIContent* aContent,
                          nsIFrame* aParent,
                          nsIFrame* aPrevInFlow)
@@ -43,7 +43,7 @@ nsSVGInnerSVGFrame::Init(nsIContent* aContent,
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::svg),
                "Content is not an SVG 'svg' element!");
 
-  return nsSVGInnerSVGFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGInnerSVGFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGInnerSVGFrame.h

@@ -26,9 +26,9 @@ public:
   NS_DECL_FRAMEARENA_HELPERS
 
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   /**

layout/svg/nsSVGMarkerFrame.cpp

@@ -49,14 +49,14 @@ nsSVGMarkerFrame::AttributeChanged(int32_t  aNameSpaceID,
 }
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGMarkerFrame::Init(nsIContent* aContent,
                        nsIFrame* aParent,
                        nsIFrame* aPrevInFlow)
 {
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::marker), "Content is not an SVG marker");
 
-  return nsSVGMarkerFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGMarkerFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGMarkerFrame.h

@@ -51,9 +51,9 @@ public:
 
   // nsIFrame interface:
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,

layout/svg/nsSVGMaskFrame.cpp

@@ -159,7 +159,7 @@ nsSVGMaskFrame::AttributeChanged(int32_t  aNameSpaceID,
 }
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGMaskFrame::Init(nsIContent* aContent,
                      nsIFrame* aParent,
                      nsIFrame* aPrevInFlow)
@@ -167,7 +167,7 @@ nsSVGMaskFrame::Init(nsIContent* aContent,
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::mask),
                "Content is not an SVG mask");
 
-  return nsSVGMaskFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGMaskFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGMaskFrame.h

@@ -44,9 +44,9 @@ public:
                               int32_t         aModType);
 
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,

layout/svg/nsSVGOuterSVGFrame.cpp

@@ -143,7 +143,7 @@ nsSVGOuterSVGFrame::nsSVGOuterSVGFrame(nsStyleContext* aContext)
   RemoveStateBits(NS_FRAME_SVG_LAYOUT);
 }
 
-NS_IMETHODIMP
+void
 nsSVGOuterSVGFrame::Init(nsIContent* aContent,
                          nsIFrame* aParent,
                          nsIFrame* aPrevInFlow)
@@ -168,7 +168,7 @@ nsSVGOuterSVGFrame::Init(nsIContent* aContent,
     AddStateBits(NS_STATE_SVG_NONDISPLAY_CHILD);
   }
 
-  nsresult rv = nsSVGOuterSVGFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGOuterSVGFrameBase::Init(aContent, aParent, aPrevInFlow);
 
   nsIDocument* doc = mContent->GetCurrentDoc();
   if (doc) {
@@ -180,8 +180,6 @@ nsSVGOuterSVGFrame::Init(nsIContent* aContent,
     // not need to be removed
     doc->AddMutationObserverUnlessExists(&sSVGMutationObserver);
   }
-
-  return rv;
 }
 
 //----------------------------------------------------------------------
@@ -921,14 +919,14 @@ NS_NewSVGOuterSVGAnonChildFrame(nsIPresShell* aPresShell,
 NS_IMPL_FRAMEARENA_HELPERS(nsSVGOuterSVGAnonChildFrame)
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGOuterSVGAnonChildFrame::Init(nsIContent* aContent,
                                   nsIFrame* aParent,
                                   nsIFrame* aPrevInFlow)
 {
   NS_ABORT_IF_FALSE(aParent->GetType() == nsGkAtoms::svgOuterSVGFrame,
                     "Unexpected parent");
-  return nsSVGOuterSVGAnonChildFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGOuterSVGAnonChildFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif
 

layout/svg/nsSVGOuterSVGFrame.h

@@ -61,9 +61,9 @@ public:
                                 const nsRect&           aDirtyRect,
                                 const nsDisplayListSet& aLists) MOZ_OVERRIDE;
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   virtual nsSplittableType GetSplittableType() const;
 
@@ -239,9 +239,9 @@ public:
   NS_DECL_FRAMEARENA_HELPERS
 
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent* aContent,
+  virtual void Init(nsIContent* aContent,
-                  nsIFrame* aParent,
+                    nsIFrame* aParent,
-                  nsIFrame* aPrevInFlow);
+                    nsIFrame* aPrevInFlow) MOZ_OVERRIDE;
 
   NS_IMETHOD GetFrameName(nsAString& aResult) const {
     return MakeFrameName(NS_LITERAL_STRING("SVGOuterSVGAnonChild"), aResult);

layout/svg/nsSVGPatternFrame.cpp

@@ -101,14 +101,14 @@ nsSVGPatternFrame::AttributeChanged(int32_t         aNameSpaceID,
 }
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGPatternFrame::Init(nsIContent* aContent,
                         nsIFrame* aParent,
                         nsIFrame* aPrevInFlow)
 {
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::pattern), "Content is not an SVG pattern");
 
-  return nsSVGPatternFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGPatternFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGPatternFrame.h

@@ -59,9 +59,9 @@ public:
                               int32_t         aModType);
 
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   /**

layout/svg/nsSVGStopFrame.cpp

@@ -31,9 +31,9 @@ public:
 
   // nsIFrame interface:
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   void BuildDisplayList(nsDisplayListBuilder*   aBuilder,
@@ -75,14 +75,14 @@ NS_IMPL_FRAMEARENA_HELPERS(nsSVGStopFrame)
 // nsIFrame methods:
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGStopFrame::Init(nsIContent* aContent,
                      nsIFrame* aParent,
                      nsIFrame* aPrevInFlow)
 {
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::stop), "Content is not a stop element");
 
-  return nsSVGStopFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGStopFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGSwitchFrame.cpp

@@ -27,9 +27,9 @@ public:
   NS_DECL_FRAMEARENA_HELPERS
 
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   /**
@@ -74,7 +74,7 @@ NS_NewSVGSwitchFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 NS_IMPL_FRAMEARENA_HELPERS(nsSVGSwitchFrame)
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGSwitchFrame::Init(nsIContent* aContent,
                        nsIFrame* aParent,
                        nsIFrame* aPrevInFlow)
@@ -82,7 +82,7 @@ nsSVGSwitchFrame::Init(nsIContent* aContent,
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::svgSwitch),
                "Content is not an SVG switch\n");
 
-  return nsSVGSwitchFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGSwitchFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGTSpanFrame.cpp

@@ -38,7 +38,7 @@ NS_QUERYFRAME_TAIL_INHERITING(nsSVGTSpanFrameBase)
 // nsIFrame methods
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGTSpanFrame::Init(nsIContent* aContent,
                       nsIFrame* aParent,
                       nsIFrame* aPrevInFlow)
@@ -63,7 +63,7 @@ nsSVGTSpanFrame::Init(nsIContent* aContent,
                  "Content is not an SVG tspan or altGlyph");
   }
 
-  return nsSVGTSpanFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGTSpanFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGTSpanFrame.h

@@ -42,9 +42,9 @@ public:
 
   // nsIFrame:
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   NS_IMETHOD  AttributeChanged(int32_t         aNameSpaceID,

layout/svg/nsSVGTextFrame.cpp

@@ -33,7 +33,7 @@ NS_IMPL_FRAMEARENA_HELPERS(nsSVGTextFrame)
 //----------------------------------------------------------------------
 // nsIFrame methods
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGTextFrame::Init(nsIContent* aContent,
                      nsIFrame* aParent,
                      nsIFrame* aPrevInFlow)
@@ -41,7 +41,7 @@ nsSVGTextFrame::Init(nsIContent* aContent,
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::text),
                "Content is not an SVG text");
 
-  return nsSVGTextFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGTextFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGTextFrame.h

@@ -28,9 +28,9 @@ public:
 
   // nsIFrame:
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   NS_IMETHOD  AttributeChanged(int32_t         aNameSpaceID,

layout/svg/nsSVGTextFrame2.cpp

@@ -2913,20 +2913,19 @@ NS_IMPL_FRAMEARENA_HELPERS(nsSVGTextFrame2)
 // ---------------------------------------------------------------------
 // nsIFrame methods
 
-NS_IMETHODIMP
+void
 nsSVGTextFrame2::Init(nsIContent* aContent,
                       nsIFrame* aParent,
                       nsIFrame* aPrevInFlow)
 {
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::text), "Content is not an SVG text");
 
-  nsresult rv = nsSVGTextFrame2Base::Init(aContent, aParent, aPrevInFlow);
+  nsSVGTextFrame2Base::Init(aContent, aParent, aPrevInFlow);
   AddStateBits((aParent->GetStateBits() &
                 (NS_STATE_SVG_NONDISPLAY_CHILD | NS_STATE_SVG_CLIPPATH_CHILD)) |
                NS_FRAME_SVG_LAYOUT | NS_FRAME_IS_SVG_TEXT);
 
   mMutationObserver.StartObserving(this);
-  return rv;
 }
 
 void

layout/svg/nsSVGTextFrame2.h

@@ -193,9 +193,9 @@ public:
   NS_DECL_FRAMEARENA_HELPERS
 
   // nsIFrame:
-  NS_IMETHOD Init(nsIContent* aContent,
+  virtual void Init(nsIContent* aContent,
-                  nsIFrame*   aParent,
+                    nsIFrame*   aParent,
-                  nsIFrame*   aPrevInFlow);
+                    nsIFrame*   aPrevInFlow) MOZ_OVERRIDE;
 
   virtual void DestroyFrom(nsIFrame* aDestructRoot) MOZ_OVERRIDE;
 

layout/svg/nsSVGTextPathFrame.cpp

@@ -29,7 +29,7 @@ NS_NewSVGTextPathFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 NS_IMPL_FRAMEARENA_HELPERS(nsSVGTextPathFrame)
 
 #ifdef DEBUG
-NS_IMETHODIMP
+void
 nsSVGTextPathFrame::Init(nsIContent* aContent,
                          nsIFrame* aParent,
                          nsIFrame* aPrevInFlow)
@@ -46,7 +46,7 @@ nsSVGTextPathFrame::Init(nsIContent* aContent,
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::textPath),
                "Content is not an SVG textPath");
 
-  return nsSVGTextPathFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGTextPathFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 

layout/svg/nsSVGTextPathFrame.h

@@ -41,9 +41,9 @@ public:
 
   // nsIFrame:
 #ifdef DEBUG
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 #endif
 
   NS_IMETHOD  AttributeChanged(int32_t         aNameSpaceID,

layout/svg/nsSVGUseFrame.cpp

@@ -31,9 +31,9 @@ public:
 
   
   // nsIFrame interface:
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   NS_IMETHOD  AttributeChanged(int32_t         aNameSpaceID,
                                nsIAtom*        aAttribute,
@@ -97,7 +97,7 @@ NS_QUERYFRAME_TAIL_INHERITING(nsSVGUseFrameBase)
 //----------------------------------------------------------------------
 // nsIFrame methods:
 
-NS_IMETHODIMP
+void
 nsSVGUseFrame::Init(nsIContent* aContent,
                     nsIFrame* aParent,
                     nsIFrame* aPrevInFlow)
@@ -108,7 +108,7 @@ nsSVGUseFrame::Init(nsIContent* aContent,
   mHasValidDimensions =
     static_cast<SVGUseElement*>(aContent)->HasValidDimensions();
 
-  return nsSVGUseFrameBase::Init(aContent, aParent, aPrevInFlow);
+  nsSVGUseFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 
 NS_IMETHODIMP

layout/tables/nsTableCellFrame.cpp

@@ -66,13 +66,13 @@ nsTableCellFrame::GetNextCell() const
   return nullptr;
 }
 
-NS_IMETHODIMP
+void
 nsTableCellFrame::Init(nsIContent*      aContent,
                        nsIFrame*        aParent,
                        nsIFrame*        aPrevInFlow)
 {
   // Let the base class do its initialization
-  nsresult rv = nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
+  nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
 
   if (GetStateBits() & NS_FRAME_FONT_INFLATION_CONTAINER) {
     AddStateBits(NS_FRAME_FONT_INFLATION_FLOW_ROOT);
@@ -85,8 +85,6 @@ nsTableCellFrame::Init(nsIContent*      aContent,
     cellFrame->GetColIndex(colIndex);
     SetColIndex(colIndex);
   }
-
-  return rv;
 }
 
 // nsIPercentHeightObserver methods

layout/tables/nsTableCellFrame.h

@@ -50,9 +50,9 @@ public:
   nsTableCellFrame(nsStyleContext* aContext);
   ~nsTableCellFrame();
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
 #ifdef ACCESSIBILITY
   virtual mozilla::a11y::AccType AccessibleType() MOZ_OVERRIDE;

layout/tables/nsTableFrame.cpp

@@ -163,7 +163,7 @@ nsTableFrame::nsTableFrame(nsStyleContext* aContext)
 NS_QUERYFRAME_HEAD(nsTableFrame)
 NS_QUERYFRAME_TAIL_INHERITING(nsContainerFrame)
 
-NS_IMETHODIMP
+void
 nsTableFrame::Init(nsIContent*      aContent,
                    nsIFrame*        aParent,
                    nsIFrame*        aPrevInFlow)
@@ -174,7 +174,7 @@ nsTableFrame::Init(nsIContent*      aContent,
                   "prev-in-flow must be of same type");
 
   // Let the base class do its processing
-  nsresult rv = nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
+  nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
 
   // see if border collapse is on, if so set it
   const nsStyleTableBorder* tableStyle = StyleTableBorder();
@@ -184,8 +184,6 @@ nsTableFrame::Init(nsIContent*      aContent,
   // Create the cell map if this frame is the first-in-flow.
   if (!aPrevInFlow) {
     mCellMap = new nsTableCellMap(*this, borderCollapse);
-    if (!mCellMap)
-      return NS_ERROR_OUT_OF_MEMORY;
   }
 
   if (aPrevInFlow) {
@@ -200,11 +198,7 @@ nsTableFrame::Init(nsIContent*      aContent,
       mTableLayoutStrategy = new BasicTableLayoutStrategy(this);
     else
       mTableLayoutStrategy = new FixedTableLayoutStrategy(this);
-    if (!mTableLayoutStrategy)
-      return NS_ERROR_OUT_OF_MEMORY;
   }
-
-  return rv;
 }
 
 nsTableFrame::~nsTableFrame()

layout/tables/nsTableFrame.h

@@ -124,9 +124,9 @@ public:
   /** sets defaults for table-specific style.
     * @see nsIFrame::Init 
     */
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow);
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   static float GetTwipsToPixels(nsPresContext* aPresContext);
 

layout/tables/nsTableRowFrame.cpp

@@ -130,15 +130,13 @@ nsTableRowFrame::~nsTableRowFrame()
 {
 }
 
-NS_IMETHODIMP
+void
 nsTableRowFrame::Init(nsIContent*      aContent,
                       nsIFrame*        aParent,
                       nsIFrame*        aPrevInFlow)
 {
-  nsresult  rv;
-
   // Let the base class do its initialization
-  rv = nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
+  nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
 
   NS_ASSERTION(NS_STYLE_DISPLAY_TABLE_ROW == StyleDisplay()->mDisplay,
                "wrong display on table row frame");
@@ -149,8 +147,6 @@ nsTableRowFrame::Init(nsIContent*      aContent,
     
     SetRowIndex(rowFrame->GetRowIndex());
   }
-
-  return rv;
 }
 
 /* virtual */ void

layout/tables/nsTableRowFrame.h

@@ -42,9 +42,9 @@ public:
 
   virtual ~nsTableRowFrame();
 
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
   /** @see nsIFrame::DidSetStyleContext */
   virtual void DidSetStyleContext(nsStyleContext* aOldStyleContext);
   

layout/xul/base/src/nsBoxFrame.cpp

@@ -158,13 +158,12 @@ nsBoxFrame::DidSetStyleContext(nsStyleContext* aOldStyleContext)
 /**
  * Initialize us. This is a good time to get the alignment of the box
  */
-NS_IMETHODIMP
+void
 nsBoxFrame::Init(nsIContent*      aContent,
                  nsIFrame*        aParent,
                  nsIFrame*        aPrevInFlow)
 {
-  nsresult  rv = nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
+  nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
-  NS_ENSURE_SUCCESS(rv, rv);
 
   if (GetStateBits() & NS_FRAME_FONT_INFLATION_CONTAINER) {
     AddStateBits(NS_FRAME_FONT_INFLATION_FLOW_ROOT);
@@ -183,9 +182,7 @@ nsBoxFrame::Init(nsIContent*      aContent,
   UpdateMouseThrough();
 
   // register access key
-  rv = RegUnregAccessKey(true);
+  RegUnregAccessKey(true);
-
-  return rv;
 }
 
 void nsBoxFrame::UpdateMouseThrough()
@@ -1844,12 +1841,10 @@ nsBoxFrame::GetFrameSizeWithMargin(nsIFrame* aBox, nsSize& aSize)
 
 // If you make changes to this function, check its counterparts
 // in nsTextBoxFrame and nsXULLabelFrame
-nsresult
+void
 nsBoxFrame::RegUnregAccessKey(bool aDoReg)
 {
-  // if we have no content, we can't do anything
+  MOZ_ASSERT(mContent);
-  if (!mContent)
-    return NS_ERROR_FAILURE;
 
   // find out what type of element this is
   nsIAtom *atom = mContent->Tag();
@@ -1861,14 +1856,14 @@ nsBoxFrame::RegUnregAccessKey(bool aDoReg)
       atom != nsGkAtoms::textbox &&
       atom != nsGkAtoms::tab &&
       atom != nsGkAtoms::radio) {
-    return NS_OK;
+    return;
   }
 
   nsAutoString accessKey;
   mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::accesskey, accessKey);
 
   if (accessKey.IsEmpty())
-    return NS_OK;
+    return;
 
   // With a valid PresContext we can get the ESM 
   // and register the access key
@@ -1879,8 +1874,6 @@ nsBoxFrame::RegUnregAccessKey(bool aDoReg)
     esm->RegisterAccessKey(mContent, key);
   else
     esm->UnregisterAccessKey(mContent, key);
-
-  return NS_OK;
 }
 
 bool

layout/xul/base/src/nsBoxFrame.h

@@ -83,9 +83,9 @@ public:
 
   // ----- public methods -------
   
-  NS_IMETHOD  Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                   nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                   nsIFrame*        asPrevInFlow) MOZ_OVERRIDE;
+                    nsIFrame*        asPrevInFlow) MOZ_OVERRIDE;
 
  
   NS_IMETHOD AttributeChanged(int32_t         aNameSpaceID,
@@ -218,7 +218,7 @@ protected:
     bool GetEventPoint(nsGUIEvent *aEvent, nsIntPoint &aPoint);
 
 protected:
-    nsresult RegUnregAccessKey(bool aDoReg);
+    void RegUnregAccessKey(bool aDoReg);
 
   NS_HIDDEN_(void) CheckBoxOrder();
 

layout/xul/base/src/nsDeckFrame.cpp

@@ -74,16 +74,14 @@ nsDeckFrame::AttributeChanged(int32_t         aNameSpaceID,
   return rv;
 }
 
-NS_IMETHODIMP
+void
 nsDeckFrame::Init(nsIContent*     aContent,
                   nsIFrame*       aParent,
                   nsIFrame*       aPrevInFlow)
 {
-  nsresult rv = nsBoxFrame::Init(aContent, aParent, aPrevInFlow);
+  nsBoxFrame::Init(aContent, aParent, aPrevInFlow);
 
   mIndex = GetSelectedIndex();
-
-  return rv;
 }
 
 void

layout/xul/base/src/nsDeckFrame.h

@@ -41,9 +41,9 @@ public:
                                            const nsRect&           aDirtyRect,
                                            const nsDisplayListSet& aLists) MOZ_OVERRIDE;
                                          
-  NS_IMETHOD Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                  nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                  nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
+                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
 
   virtual nsIAtom* GetType() const MOZ_OVERRIDE;
 

layout/xul/base/src/nsImageBoxFrame.cpp

@@ -179,7 +179,7 @@ nsImageBoxFrame::DestroyFrom(nsIFrame* aDestructRoot)
 }
 
 
-NS_IMETHODIMP
+void
 nsImageBoxFrame::Init(nsIContent*      aContent,
                       nsIFrame*        aParent,
                       nsIFrame*        aPrevInFlow)
@@ -193,13 +193,11 @@ nsImageBoxFrame::Init(nsIContent*      aContent,
   }
 
   mSuppressStyleCheck = true;
-  nsresult rv = nsLeafBoxFrame::Init(aContent, aParent, aPrevInFlow);
+  nsLeafBoxFrame::Init(aContent, aParent, aPrevInFlow);
   mSuppressStyleCheck = false;
 
   UpdateLoadFlags();
   UpdateImage();
-
-  return rv;
 }
 
 void

layout/xul/base/src/nsImageBoxFrame.h

@@ -50,9 +50,9 @@ public:
 
   friend nsIFrame* NS_NewImageBoxFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);
 
-  NS_IMETHOD  Init(nsIContent*      aContent,
+  virtual void Init(nsIContent*      aContent,
-                   nsIFrame*        aParent,
+                    nsIFrame*        aParent,
-                   nsIFrame*        asPrevInFlow) MOZ_OVERRIDE;
+                    nsIFrame*        asPrevInFlow) MOZ_OVERRIDE;
 
   NS_IMETHOD AttributeChanged(int32_t aNameSpaceID,
                               nsIAtom* aAttribute,

layout/xul/base/src/nsLeafBoxFrame.cpp

@@ -55,22 +55,19 @@ nsLeafBoxFrame::GetBoxName(nsAutoString& aName)
 /**
  * Initialize us. This is a good time to get the alignment of the box
  */
-NS_IMETHODIMP
+void
 nsLeafBoxFrame::Init(
               nsIContent*      aContent,
               nsIFrame*        aParent,
               nsIFrame*        aPrevInFlow)
 {
-  nsresult  rv = nsLeafFrame::Init(aContent, aParent, aPrevInFlow);
+  nsLeafFrame::Init(aContent, aParent, aPrevInFlow);
-  NS_ENSURE_SUCCESS(rv, rv);
 
   if (GetStateBits() & NS_FRAME_FONT_INFLATION_CONTAINER) {
     AddStateBits(NS_FRAME_FONT_INFLATION_FLOW_ROOT);
   }
 
   UpdateMouseThrough();
-
-  return rv;
 }
 
 NS_IMETHODIMP

layout/xul/base/src/nsLeafBoxFrame.h

@@ -56,10 +56,9 @@ public:
 
   NS_IMETHOD CharacterDataChanged(CharacterDataChangeInfo* aInfo) MOZ_OVERRIDE;
 
-  NS_IMETHOD  Init(
+  virtual void Init(nsIContent*      aContent,
-               nsIContent*      aContent,
+                    nsIFrame*        aParent,
-               nsIFrame*        aParent,
+                    nsIFrame*        asPrevInFlow) MOZ_OVERRIDE;
-               nsIFrame*        asPrevInFlow) MOZ_OVERRIDE;
 
   virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                                 const nsRect&           aDirtyRect,

layout/xul/base/src/nsListBoxBodyFrame.cpp

@@ -176,13 +176,12 @@ NS_QUERYFRAME_TAIL_INHERITING(nsBoxFrame)
 
 ////////// nsIFrame /////////////////
 
-NS_IMETHODIMP
+void
 nsListBoxBodyFrame::Init(nsIContent*     aContent,
                          nsIFrame*       aParent, 
                          nsIFrame*       aPrevInFlow)
 {
-  nsresult rv = nsBoxFrame::Init(aContent, aParent, aPrevInFlow);
+  nsBoxFrame::Init(aContent, aParent, aPrevInFlow);
-  NS_ENSURE_SUCCESS(rv, rv);
   nsIScrollableFrame* scrollFrame = nsLayoutUtils::GetScrollableFrameFor(this);
   if (scrollFrame) {
     nsIFrame* verticalScrollbar = scrollFrame->GetScrollbarBox(true);
@@ -194,8 +193,6 @@ nsListBoxBodyFrame::Init(nsIContent*     aContent,
   nsRefPtr<nsFontMetrics> fm;
   nsLayoutUtils::GetFontMetricsForFrame(this, getter_AddRefs(fm));
   mRowHeight = fm->MaxHeight();
-
-  return rv;
 }
 
 void

layout/xul/base/src/nsListBoxBodyFrame.h

@@ -48,9 +48,9 @@ public:
                                           nsStyleContext* aContext);
   
   // nsIFrame
-  NS_IMETHOD Init(nsIContent*     aContent,
+  virtual void Init(nsIContent*     aContent,
-                  nsIFrame*       aParent, 
+                    nsIFrame*       aParent, 
-                  nsIFrame*       aPrevInFlow) MOZ_OVERRIDE;
+                    nsIFrame*       aPrevInFlow) MOZ_OVERRIDE;
   virtual void DestroyFrom(nsIFrame* aDestructRoot) MOZ_OVERRIDE;
 
   NS_IMETHOD AttributeChanged(int32_t aNameSpaceID, nsIAtom* aAttribute, int32_t aModType) MOZ_OVERRIDE;

layout/xul/base/src/nsMenuBarFrame.cpp

@@ -59,18 +59,16 @@ nsMenuBarFrame::nsMenuBarFrame(nsIPresShell* aShell, nsStyleContext* aContext):
 {
 } // cntr
 
-NS_IMETHODIMP
+void
 nsMenuBarFrame::Init(nsIContent*      aContent,
                      nsIFrame*        aParent,
                      nsIFrame*        aPrevInFlow)
 {
-  nsresult  rv = nsBoxFrame::Init(aContent, aParent, aPrevInFlow);
+  nsBoxFrame::Init(aContent, aParent, aPrevInFlow);
 
   // Create the menu bar listener.
   mMenuBarListener = new nsMenuBarListener(this);
-  NS_IF_ADDREF(mMenuBarListener);
+  NS_ADDREF(mMenuBarListener);
-  if (! mMenuBarListener)
-    return NS_ERROR_OUT_OF_MEMORY;
 
   // Hook up the menu bar as a key listener on the whole document.  It will see every
   // key press that occurs, but after everyone else does.
@@ -89,8 +87,6 @@ nsMenuBarFrame::Init(nsIContent*      aContent,
   target->AddEventListener(NS_LITERAL_STRING("mousedown"), mMenuBarListener, true);
   target->AddEventListener(NS_LITERAL_STRING("mousedown"), mMenuBarListener, false);
   target->AddEventListener(NS_LITERAL_STRING("blur"), mMenuBarListener, true);   
-
-  return rv;
 }
 
 NS_IMETHODIMP