Bug 1177614 - Provide a utility method on nsHTMLReflowState to return the computed size including border-padding, for use as a container for logical coordinate conversions, or zero if unconstrained. r=dholbert

layout/forms/nsComboboxControlFrame.cpp

@@ -866,8 +866,8 @@ nsComboboxControlFrame::Reflow(nsPresContext*          aPresContext,
 
   // The button should occupy the same space as a scrollbar
   WritingMode wm = aReflowState.GetWritingMode();
-  nscoord containerWidth = aReflowState.ComputedWidth() +
-    aReflowState.ComputedPhysicalBorderPadding().LeftRight();
+  nscoord containerWidth =
+    aReflowState.ComputedSizeAsContainerIfConstrained().width;
   LogicalRect buttonRect = mButtonFrame->GetLogicalRect(containerWidth);
 
   buttonRect.IStart(wm) =

layout/generic/nsHTMLReflowState.cpp

@@ -1266,8 +1266,7 @@ nsHTMLReflowState::CalculateHypotheticalBox(nsPresContext*    aPresContext,
   // relatively positioned...
   WritingMode cbwm = cbrs->GetWritingMode();
   nscoord containerWidth = containingBlock->GetStateBits() & NS_FRAME_IN_REFLOW
-    ? cbrs->ComputedWidth() +
-      cbrs->ComputedLogicalBorderPadding().LeftRight(cbwm)
+    ? cbrs->ComputedSizeAsContainerIfConstrained().width
     : containingBlock->GetSize().width;
   LogicalPoint placeholderOffset(wm, aPlaceholderFrame->GetOffsetTo(containingBlock),
                                  containerWidth);

layout/generic/nsHTMLReflowState.h

@@ -447,6 +447,17 @@ struct nsHTMLReflowState : public nsCSSOffsetState {
   void SetComputedLogicalOffsets(const LogicalMargin& aOffsets)
     { mComputedOffsets = aOffsets.GetPhysicalMargin(mWritingMode); }
 
+  // Return the state's computed size including border-padding, with
+  // unconstrained dimensions replaced by zero.
+  nsSize ComputedSizeAsContainerIfConstrained() const {
+    const nscoord wd = ComputedWidth();
+    const nscoord ht = ComputedHeight();
+    return nsSize(wd == NS_UNCONSTRAINEDSIZE
+                  ? 0 : wd + ComputedPhysicalBorderPadding().LeftRight(),
+                  ht == NS_UNCONSTRAINEDSIZE
+                  ? 0 : ht + ComputedPhysicalBorderPadding().TopBottom());
+  }
+
 private:
   // the available width in which to reflow the frame. The space
   // represents the amount of room for the frame's margin, border,

layout/tables/nsTableCellFrame.cpp

@@ -944,14 +944,9 @@ nsTableCellFrame::Reflow(nsPresContext*           aPresContext,
     kidReflowState.SetBResize(true);
   }
 
-  nscoord containerWidth;
-  if (aReflowState.ComputedWidth() == NS_UNCONSTRAINEDSIZE) {
-    containerWidth = 0; // avoid passing unconstrained container width to
-                        // ReflowChild; but position will not be valid
-  } else {
-    containerWidth = aReflowState.ComputedWidth() +
-      aReflowState.ComputedPhysicalBorderPadding().LeftRight();
-  }
+  nscoord containerWidth =
+    aReflowState.ComputedSizeAsContainerIfConstrained().width;
+
   LogicalPoint kidOrigin(wm, borderPadding.IStart(wm),
                          borderPadding.BStart(wm));
   nsRect origRect = firstKid->GetRect();

layout/tables/nsTableFrame.cpp

@@ -2973,19 +2973,11 @@ nsTableFrame::ReflowChildren(nsTableReflowState& aReflowState,
 
   nsIFrame* prevKidFrame = nullptr;
   WritingMode wm = aReflowState.reflowState.GetWritingMode();
-  nscoord containerWidth = aReflowState.reflowState.ComputedWidth();
-  if (containerWidth == NS_UNCONSTRAINEDSIZE) {
-    NS_WARN_IF_FALSE(wm.IsVertical(),
-                     "shouldn't have unconstrained width in horizontal mode");
-    // We won't know the containerWidth until we've reflowed our contents,
-    // so use zero for now; in vertical-rl mode, this will mean the children
-    // are misplaced in the block-direction, and will need to be moved
-    // rightwards by the true containerWidth once we know it.
-    containerWidth = 0;
-  } else {
-    containerWidth +=
-      aReflowState.reflowState.ComputedPhysicalBorderPadding().LeftRight();
-  }
+  NS_WARN_IF_FALSE(wm.IsVertical() || NS_UNCONSTRAINEDSIZE !=
+                                      aReflowState.reflowState.ComputedWidth(),
+                   "shouldn't have unconstrained width in horizontal mode");
+  nscoord containerWidth =
+    aReflowState.reflowState.ComputedSizeAsContainerIfConstrained().width;
 
   nsPresContext* presContext = PresContext();
   // XXXldb Should we be checking constrained height instead?
@@ -3388,12 +3380,8 @@ nsTableFrame::DistributeBSizeToRows(const nsHTMLReflowState& aReflowState,
   WritingMode wm = aReflowState.GetWritingMode();
   LogicalMargin borderPadding = GetChildAreaOffset(wm, &aReflowState);
 
-  nscoord containerWidth = aReflowState.ComputedWidth();
-  if (containerWidth == NS_UNCONSTRAINEDSIZE) {
-    containerWidth = 0;
-  } else {
-    containerWidth += aReflowState.ComputedPhysicalBorderPadding().LeftRight();
-  }
+  nscoord containerWidth =
+    aReflowState.ComputedSizeAsContainerIfConstrained().width;
 
   RowGroupArray rowGroups;
   OrderRowGroups(rowGroups);

layout/tables/nsTableRowFrame.cpp

@@ -817,12 +817,8 @@ nsTableRowFrame::ReflowChildren(nsPresContext*           aPresContext,
 
   // Reflow each of our existing cell frames
   WritingMode wm = aReflowState.GetWritingMode();
-  nscoord containerWidth = aReflowState.ComputedWidth();
-  if (containerWidth == NS_UNCONSTRAINEDSIZE) {
-    containerWidth = 0; // cell positions will not yet be correct
-  } else {
-    containerWidth += aReflowState.ComputedPhysicalBorderPadding().LeftRight();
-  }
+  nscoord containerWidth =
+    aReflowState.ComputedSizeAsContainerIfConstrained().width;
 
   for (nsIFrame* kidFrame : mFrames) {
     nsTableCellFrame *cellFrame = do_QueryFrame(kidFrame);

layout/tables/nsTableRowGroupFrame.cpp

@@ -346,14 +346,8 @@ nsTableRowGroupFrame::ReflowChildren(nsPresContext*         aPresContext,
   // get the necessary containerWidth for placing our kids
   bool needToCalcRowBSizes = reflowAllKids || wm.IsVerticalRL();
 
-  nscoord containerWidth = aReflowState.reflowState.ComputedWidth();
-  if (containerWidth == NS_UNCONSTRAINEDSIZE) {
-    containerWidth = 0; // we can't position frames correctly in RTL yet,
-                        // so they will need to be adjusted later
-  } else {
-    containerWidth +=
-      aReflowState.reflowState.ComputedPhysicalBorderPadding().LeftRight();
-  }
+  nscoord containerWidth =
+    aReflowState.reflowState.ComputedSizeAsContainerIfConstrained().width;
 
   nsIFrame *prevKidFrame = nullptr;
   for (nsIFrame* kidFrame = mFrames.FirstChild(); kidFrame;