Backed out changeset 7be71c699b85 (bug 984226) for crashtest asserts.

layout/base/RestyleManager.cpp

@@ -687,8 +687,7 @@ RestyleManager::ProcessRestyledFrames(nsStyleChangeList& aChangeList)
         // FinishAndStoreOverflow on it:
         hint = NS_SubtractHint(hint,
                  NS_CombineHint(nsChangeHint_UpdateOverflow,
-                   NS_CombineHint(nsChangeHint_ChildrenOnlyTransform,
+                                nsChangeHint_ChildrenOnlyTransform));
-                                  nsChangeHint_UpdatePostTransformOverflow)));
       }
 
       if (hint & nsChangeHint_UpdateEffects) {
@@ -716,10 +715,7 @@ RestyleManager::ProcessRestyledFrames(nsStyleChangeList& aChangeList)
       NS_ASSERTION(!(hint & nsChangeHint_ChildrenOnlyTransform) ||
                    (hint & nsChangeHint_UpdateOverflow),
                    "nsChangeHint_UpdateOverflow should be passed too");
-      if (!didReflowThisFrame &&
+      if ((hint & nsChangeHint_UpdateOverflow) && !didReflowThisFrame) {
-          (hint & (nsChangeHint_UpdateOverflow |
-                   nsChangeHint_UpdatePostTransformOverflow))) {
-        OverflowChangedTracker::ChangeKind changeKind;
         if (hint & nsChangeHint_ChildrenOnlyTransform) {
           // The overflow areas of the child frames need to be updated:
           nsIFrame* hintFrame = GetFrameForChildrenOnlyTransformHint(frame);
@@ -737,7 +733,7 @@ RestyleManager::ProcessRestyledFrames(nsStyleChangeList& aChangeList)
             // updating overflows since that will happen when it's reflowed.
             if (!(childFrame->GetStateBits() &
                   (NS_FRAME_IS_DIRTY | NS_FRAME_HAS_DIRTY_CHILDREN))) {
-              mOverflowChangedTracker.AddFrame(childFrame, OverflowChangedTracker::CHILDREN_CHANGED);
+              mOverflowChangedTracker.AddFrame(childFrame);
             }
             NS_ASSERTION(!nsLayoutUtils::GetNextContinuationOrIBSplitSibling(childFrame),
                          "SVG frames should not have continuations "
@@ -750,17 +746,9 @@ RestyleManager::ProcessRestyledFrames(nsStyleChangeList& aChangeList)
         // overflows since that will happen when it's reflowed.
         if (!(frame->GetStateBits() &
               (NS_FRAME_IS_DIRTY | NS_FRAME_HAS_DIRTY_CHILDREN))) {
-          // If we have both nsChangeHint_UpdateOverflow and
-          // nsChangeHint_UpdatePostTransformOverflow, CHILDREN_CHANGED
-          // is selected as it is stronger.
-          if (hint & nsChangeHint_UpdateOverflow) {
-            changeKind = OverflowChangedTracker::CHILDREN_CHANGED;
-          } else {
-            changeKind = OverflowChangedTracker::TRANSFORM_CHANGED;
-          }
           for (nsIFrame *cont = frame; cont; cont =
                  nsLayoutUtils::GetNextContinuationOrIBSplitSibling(cont)) {
-            mOverflowChangedTracker.AddFrame(cont, changeKind);
+            mOverflowChangedTracker.AddFrame(cont);
           }
         }
       }

layout/base/RestyleTracker.h

@@ -28,19 +28,6 @@ class RestyleManager;
 class OverflowChangedTracker
 {
 public:
-  enum ChangeKind {
-    /**
-     * The overflow areas of children have changed
-     * and we need to call UpdateOverflow on the frame.
-     */
-    CHILDREN_CHANGED,
-    /**
-     * The frame was explicitly added as a result of
-     * nsChangeHint_UpdatePostTransformOverflow and hence may have had a style
-     * change that changes its geometry relative to parent, without reflowing.
-     */
-    TRANSFORM_CHANGED
-  };
 
   OverflowChangedTracker() :
     mSubtreeRoot(nullptr)
@@ -62,19 +49,14 @@ public:
    * If the overflow area changes, then UpdateOverflow will also
    * be called on the parent.
    */
-  void AddFrame(nsIFrame* aFrame, ChangeKind aChangeKind) {
+  void AddFrame(nsIFrame* aFrame) {
     uint32_t depth = aFrame->GetDepthInFrameTree();
-    Entry *entry = nullptr;
+    if (mEntryList.empty() ||
-    if (!mEntryList.empty()) {
+        !mEntryList.find(Entry(aFrame, depth))) {
-      entry = mEntryList.find(Entry(aFrame, depth));
+      // All frames in mEntryList at this stage have STYLE_CHANGED so we don't
-    }
+      // need to worry about setting the STYLE_CHANGED flag if 'find'
-    if (entry == nullptr) {
+      // returns true.
-      // Add new entry
+      mEntryList.insert(new Entry(aFrame, depth, STYLE_CHANGED));
-      mEntryList.insert(new Entry(aFrame, depth, aChangeKind));
-    } else if (aChangeKind == CHILDREN_CHANGED) {
-      // Update existing entry.  CHILDREN_CHANGED is stronger than
-      // TRANSFORM_CHANGED and will replace CHILDREN_CHANGED value.
-      entry->mChangeKind = CHILDREN_CHANGED;
     }
   }
 
@@ -112,49 +94,38 @@ public:
       Entry *entry = mEntryList.removeMin();
       nsIFrame *frame = entry->mFrame;
 
-      bool overflowChanged = false;
+      bool overflowChanged;
-      if (entry->mChangeKind == CHILDREN_CHANGED) {
+      if (entry->mFlags & CHILDREN_CHANGED) {
         // Need to union the overflow areas of the children.
         overflowChanged = frame->UpdateOverflow();
       } else {
-        // Take a faster path that doesn't require unioning the overflow areas
+        nsOverflowAreas* pre = static_cast<nsOverflowAreas*>
-        // of our children.
+          (frame->Properties().Get(frame->PreTransformOverflowAreasProperty()));
-
+        if (pre) {
-#ifdef DEBUG
+          // Since we have the pre-transform-overflow-areas, we can take a
-        bool hasInitialOverflowPropertyApplied = false;
+          // faster path that doesn't require unioning the overflow areas
-        frame->Properties().Get(nsIFrame::DebugInitialOverflowPropertyApplied(),
+          // of our children.
-                                 &hasInitialOverflowPropertyApplied);
-        NS_ASSERTION(hasInitialOverflowPropertyApplied,
-                     "InitialOverflowProperty must be set first.");
-#endif
-
-        nsOverflowAreas* overflow = 
-          static_cast<nsOverflowAreas*>(frame->Properties().Get(nsIFrame::InitialOverflowProperty()));
-        if (overflow) {
           // FinishAndStoreOverflow will change the overflow areas passed in,
           // so make a copy.
-          nsOverflowAreas overflowCopy = *overflow;
+          nsOverflowAreas overflowAreas = *pre;
-          frame->FinishAndStoreOverflow(overflowCopy, frame->GetSize());
+          frame->FinishAndStoreOverflow(overflowAreas, frame->GetSize());
+          // We can't tell if the overflow changed, so be conservative
+          overflowChanged = true;
         } else {
-          nsRect bounds(nsPoint(0, 0), frame->GetSize());
+          // We can't take the faster path here. Do it the hard way.
-          nsOverflowAreas boundsOverflow;
+          overflowChanged = frame->UpdateOverflow();
-          boundsOverflow.SetAllTo(bounds);
-          frame->FinishAndStoreOverflow(boundsOverflow, bounds.Size());
         }
-
-        // We can't tell if the overflow changed, so be conservative
-        overflowChanged = true;
       }
 
       // If the frame style changed (e.g. positioning offsets)
       // then we need to update the parent with the overflow areas of its
       // children.
-      if (overflowChanged) {
+      if (overflowChanged || (entry->mFlags & STYLE_CHANGED)) {
         nsIFrame *parent = frame->GetParent();
         if (parent && parent != mSubtreeRoot) {
           Entry* parentEntry = mEntryList.find(Entry(parent, entry->mDepth - 1));
           if (parentEntry) {
-            parentEntry->mChangeKind = CHILDREN_CHANGED;
+            parentEntry->mFlags |= CHILDREN_CHANGED;
           } else {
             mEntryList.insert(new Entry(parent, entry->mDepth - 1, CHILDREN_CHANGED));
           }
@@ -165,12 +136,26 @@ public:
   }
   
 private:
+  enum {
+    /**
+     * Set if the overflow areas of children have changed so we need to call
+     * UpdateOverflow on the frame.
+     */
+    CHILDREN_CHANGED = 0x01,
+    /**
+     * True if the frame was explicitly added and hence may have had a style
+     * change that changes its geometry relative to parent, without reflowing.
+     * In this case we must update overflow on the frame's parent even if
+     * this frame's overflow did not change.
+     */
+    STYLE_CHANGED = 0x02
+  };
   struct Entry : SplayTreeNode<Entry>
   {
-    Entry(nsIFrame* aFrame, uint32_t aDepth, ChangeKind aChangeKind = CHILDREN_CHANGED)
+    Entry(nsIFrame* aFrame, uint32_t aDepth, uint8_t aFlags = 0)
       : mFrame(aFrame)
       , mDepth(aDepth)
-      , mChangeKind(aChangeKind)
+      , mFlags(aFlags)
     {}
 
     bool operator==(const Entry& aOther) const
@@ -204,7 +189,7 @@ private:
     nsIFrame* mFrame;
     /* Depth in the frame tree */
     uint32_t mDepth;
-    ChangeKind mChangeKind;
+    uint8_t mFlags;
   };
 
   /* A list of frames to process, sorted by their depth in the frame tree */

layout/base/nsChangeHint.h

@@ -72,23 +72,17 @@ enum nsChangeHint {
   nsChangeHint_ReconstructFrame = 0x400,
 
   /**
-   * The frame's overflow area has changed, either through a change in its
+   * The frame's effect on its ancestors' overflow areas has changed,
-   * transform or a change in its position. Does not update any descendant
+   * either through a change in its transform or a change in its position.
-   * frames.
-   */
-  nsChangeHint_UpdateOverflow = 0x800,
-
-  /**
-   * The frame's overflow area has changed, through a change in its transform.
    * Does not update any descendant frames.
    */
-  nsChangeHint_UpdatePostTransformOverflow = 0x1000,
+  nsChangeHint_UpdateOverflow = 0x800,
 
   /**
    * The children-only transform of an SVG frame changed, requiring the
    * overflow rects of the frame's immediate children to be updated.
    */
-  nsChangeHint_ChildrenOnlyTransform = 0x2000,
+  nsChangeHint_ChildrenOnlyTransform = 0x1000,
 
   /**
    * The frame's offsets have changed, while its dimensions might have
@@ -100,7 +94,7 @@ enum nsChangeHint {
    * nsChangeHint_UpdateOverflow in order to get the overflow areas of
    * the ancestors updated as well.
    */
-  nsChangeHint_RecomputePosition = 0x4000,
+  nsChangeHint_RecomputePosition = 0x2000,
 
   /**
    * Behaves like ReconstructFrame, but only if the frame has descendants
@@ -108,7 +102,7 @@ enum nsChangeHint {
    * has changed whether the frame is a container for fixed-pos or abs-pos
    * elements, but reframing is otherwise not needed.
    */
-  nsChangeHint_AddOrRemoveTransform = 0x8000,
+  nsChangeHint_AddOrRemoveTransform = 0x4000,
 
   /**
    * This change hint has *no* change handling behavior.  However, it
@@ -116,13 +110,13 @@ enum nsChangeHint {
    * changes, and it's inherited by a child, that might require a reflow
    * due to the border-width change on the child.
    */
-  nsChangeHint_BorderStyleNoneChange = 0x10000,
+  nsChangeHint_BorderStyleNoneChange = 0x8000,
 
   /**
    * SVG textPath needs to be recomputed because the path has changed.
    * This means that the glyph positions of the text need to be recomputed.
    */
-  nsChangeHint_UpdateTextPath = 0x20000
+  nsChangeHint_UpdateTextPath = 0x10000
 
   // IMPORTANT NOTE: When adding new hints, consider whether you need to
   // add them to NS_HintsNotHandledForDescendantsIn() below.
@@ -178,7 +172,6 @@ inline bool NS_IsHintSubset(nsChangeHint aSubset, nsChangeHint aSuperSet) {
           nsChangeHint_UpdateEffects | \
           nsChangeHint_UpdateOpacityLayer | \
           nsChangeHint_UpdateOverflow | \
-          nsChangeHint_UpdatePostTransformOverflow | \
           nsChangeHint_ChildrenOnlyTransform | \
           nsChangeHint_RecomputePosition | \
           nsChangeHint_AddOrRemoveTransform | \
@@ -192,7 +185,6 @@ inline nsChangeHint NS_HintsNotHandledForDescendantsIn(nsChangeHint aChangeHint)
     nsChangeHint_UpdateEffects |
     nsChangeHint_UpdateOpacityLayer |
     nsChangeHint_UpdateOverflow |
-    nsChangeHint_UpdatePostTransformOverflow |
     nsChangeHint_ChildrenOnlyTransform |
     nsChangeHint_RecomputePosition |
     nsChangeHint_AddOrRemoveTransform |

layout/generic/StickyScrollContainer.cpp

@@ -371,12 +371,9 @@ StickyScrollContainer::UpdatePositions(nsPoint aScrollPosition,
     // nsIFrame::Init.
     PositionContinuations(f);
 
-    f = f->GetParent();
+    for (nsIFrame* cont = f; cont;
-    if (f != aSubtreeRoot) {
+         cont = nsLayoutUtils::GetNextContinuationOrIBSplitSibling(cont)) {
-      for (nsIFrame* cont = f; cont;
+      oct.AddFrame(cont);
-           cont = nsLayoutUtils::GetNextContinuationOrIBSplitSibling(cont)) {
-        oct.AddFrame(cont, OverflowChangedTracker::CHILDREN_CHANGED);
-      }
     }
   }
   oct.Flush();

layout/generic/nsFrame.cpp

@@ -7182,28 +7182,18 @@ nsIFrame::FinishAndStoreOverflow(nsOverflowAreas& aOverflowAreas,
                "Don't call - overflow rects not maintained on these SVG frames");
 
   nsRect bounds(nsPoint(0, 0), aNewSize);
-  // Store the passed in overflow area if we are a preserve-3d frame or we have
+  // Store the passed in overflow area if we are a preserve-3d frame,
-  // a transform, and it's not just the frame bounds.
+  // and it's not just the frame bounds.
-  if (Preserves3D() || HasPerspective() || IsTransformed()) {
+  if ((Preserves3D() || HasPerspective()) && (!aOverflowAreas.VisualOverflow().IsEqualEdges(bounds) ||
-    if (!aOverflowAreas.VisualOverflow().IsEqualEdges(bounds) ||
+                        !aOverflowAreas.ScrollableOverflow().IsEqualEdges(bounds))) {
-        !aOverflowAreas.ScrollableOverflow().IsEqualEdges(bounds)) {
+    nsOverflowAreas* initial =
-
+      static_cast<nsOverflowAreas*>(Properties().Get(nsIFrame::InitialOverflowProperty()));
-      nsOverflowAreas* initial =
+    if (!initial) {
-        static_cast<nsOverflowAreas*>(Properties().Get(nsIFrame::InitialOverflowProperty()));
+      Properties().Set(nsIFrame::InitialOverflowProperty(),
-      if (!initial) {
+                       new nsOverflowAreas(aOverflowAreas));
-        Properties().Set(nsIFrame::InitialOverflowProperty(),
+    } else if (initial != &aOverflowAreas) {
-                         new nsOverflowAreas(aOverflowAreas));
+      *initial = aOverflowAreas;
-      } else if (initial != &aOverflowAreas) {
-        *initial = aOverflowAreas;
-      }
     }
-#ifdef DEBUG
-    Properties().Set(nsIFrame::DebugInitialOverflowPropertyApplied(), nullptr);
-#endif
-  } else {
-#ifdef DEBUG
-  Properties().Delete(nsIFrame::DebugInitialOverflowPropertyApplied());
-#endif
   }
 
   // This is now called FinishAndStoreOverflow() instead of 

layout/generic/nsIFrame.h

@@ -877,17 +877,10 @@ public:
                             DestroyOverflowAreas)
 
   // The initial overflow area passed to FinishAndStoreOverflow. This is only set
-  // on frames that Preserve3D() or HasPerspective() or IsTransformed(), and
+  // on frames that Preserve3D(), and when at least one of the overflow areas
-  // when at least one of the overflow areas differs from the frame bound rect.
+  // differs from the frame bound rect.
   NS_DECLARE_FRAME_PROPERTY(InitialOverflowProperty, DestroyOverflowAreas)
 
-#ifdef DEBUG
-  // InitialOverflowPropertyDebug is added to the frame to indicate that either
-  // the InitialOverflowProperty has been stored or the InitialOverflowProperty
-  // has been suppressed due to being set to the default value (frame bounds)
-  NS_DECLARE_FRAME_PROPERTY(DebugInitialOverflowPropertyApplied, nullptr)
-#endif
-
   NS_DECLARE_FRAME_PROPERTY(UsedMarginProperty, DestroyMargin)
   NS_DECLARE_FRAME_PROPERTY(UsedPaddingProperty, DestroyMargin)
   NS_DECLARE_FRAME_PROPERTY(UsedBorderProperty, DestroyMargin)

layout/style/nsStyleStruct.cpp

@@ -2524,7 +2524,7 @@ nsChangeHint nsStyleDisplay::CalcDifference(const nsStyleDisplay& aOther) const
     if (!mSpecifiedTransform != !aOther.mSpecifiedTransform ||
         (mSpecifiedTransform &&
          *mSpecifiedTransform != *aOther.mSpecifiedTransform)) {
-      NS_UpdateHint(hint, NS_CombineHint(nsChangeHint_UpdatePostTransformOverflow,
+      NS_UpdateHint(hint, NS_CombineHint(nsChangeHint_UpdateOverflow,
                                          nsChangeHint_UpdateTransformLayer));
     }
 

layout/style/nsStyleStruct.h

@@ -1901,7 +1901,6 @@ struct nsStyleDisplay {
                         nsChangeHint_UpdateOpacityLayer |
                         nsChangeHint_UpdateTransformLayer |
                         nsChangeHint_UpdateOverflow |
-                        nsChangeHint_UpdatePostTransformOverflow |
                         nsChangeHint_AddOrRemoveTransform);
   }
   static nsChangeHint MaxDifferenceNeverInherited() {

layout/tables/nsTableFrame.cpp

@@ -1955,7 +1955,7 @@ nsTableFrame::FixupPositionedTableParts(nsPresContext*           aPresContext,
     // FIXME: Unconditionally using NS_UNCONSTRAINEDSIZE for the height and
     // ignoring any change to the reflow status aren't correct. We'll never
     // paginate absolutely positioned frames.
-    overflowTracker.AddFrame(positionedPart, OverflowChangedTracker::CHILDREN_CHANGED);
+    overflowTracker.AddFrame(positionedPart);
     nsFrame* positionedFrame = static_cast<nsFrame*>(positionedPart);
     positionedFrame->FinishReflowWithAbsoluteFrames(PresContext(),
                                                     desiredSize,