flexbox: incorrect flexbox height with overflow:auto on flex item

Source/core/rendering/RenderFlexibleBox.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 1086 matching lines @@
             resetAutoMarginsAndLogicalTopInCrossAxis(child);
         }
         // We may have already forced relayout for orthogonal flowing children in preferredMainAxisContentExtentForChild.
         bool forceChildRelayout = relayoutChildren && !childPreferredMainAxisContentExtentRequiresLayout(child, hasInfiniteLineLength);
         updateBlockChildDirtyBitsBeforeLayout(forceChildRelayout, child);
         child->layoutIfNeeded();
 
         updateAutoMarginsInMainAxis(child, autoMarginOffset);
 
         LayoutUnit childCrossAxisMarginBoxExtent;
+        LayoutUnit crossAxisScrollbarExtentForChild = !isColumnFlow() ? child->scrollbarLogicalHeight() : child->instrinsicScrollbarLogicalWidth();

[cbiesinger, 2014/08/07 02:57:01]

I'd really prefer you to flip the ?: around so you don't need the negation here.

isColumnFlow() ? child->instrinsicScrollbarLogicalWidth() :
child->scrollbarLogicalHeight()

But why not follow the example from the crossAxis* functions and write this
using isHorizontalFlow and the non-logical height/width?

[harpreet.sk, 2014/08/07 12:46:39]

Modified the solution to use isHorizontalFlow and the non-logical height/width 

         if (alignmentForChild(child) == ItemPositionBaseline && !hasAutoMarginsInCrossAxis(child)) {
             LayoutUnit ascent = marginBoxAscentForChild(child);
             LayoutUnit descent = (crossAxisMarginExtentForChild(child) + crossAxisExtentForChild(child)) - ascent;
 
             maxAscent = std::max(maxAscent, ascent);
             maxDescent = std::max(maxDescent, descent);
 
-            childCrossAxisMarginBoxExtent = maxAscent + maxDescent;
+            childCrossAxisMarginBoxExtent = maxAscent + maxDescent + crossAxisScrollbarExtentForChild;

[tony, 2014/08/06 16:47:22]

I don't see any align-item baseline test cases that go through this code path. 
Please add some.

[harpreet.sk, 2014/08/07 12:46:39]

Actually we should not add crossAxisScrollbarExtentForChild for baseline cases
as while computing descent it takes crossAxisExtentForChild which will include
the scrollbar height.

I added the test cases of align-item baseline just to make sure that they are
working fine.

         } else {
-            childCrossAxisMarginBoxExtent = crossAxisIntrinsicExtentForChild(child) + crossAxisMarginExtentForChild(child);
+            childCrossAxisMarginBoxExtent = crossAxisIntrinsicExtentForChild(child) + crossAxisMarginExtentForChild(child) + crossAxisScrollbarExtentForChild;
         }
         if (!isColumnFlow())
             setLogicalHeight(std::max(logicalHeight(), crossAxisOffset + flowAwareBorderAfter() + flowAwarePaddingAfter() + childCrossAxisMarginBoxExtent + crossAxisScrollbarExtent()));
         maxChildCrossAxisExtent = std::max(maxChildCrossAxisExtent, childCrossAxisMarginBoxExtent);
 
         mainAxisOffset += flowAwareMarginStartForChild(child);
 
         LayoutUnit childMainExtent = mainAxisExtentForChild(child);
         // In an RTL column situation, this will apply the margin-right/margin-end on the left.
         // This will be fixed later in flipForRightToLeftColumn.
@@ skipping 270 matching lines @@
             ASSERT(child);
             LayoutUnit lineCrossAxisExtent = lineContexts[lineNumber].crossAxisExtent;
             LayoutUnit originalOffset = lineContexts[lineNumber].crossAxisOffset - crossAxisStartEdge;
             LayoutUnit newOffset = contentExtent - originalOffset - lineCrossAxisExtent;
             adjustAlignmentForChild(child, newOffset - originalOffset);
         }
     }
 }
 
 }