availableLogicalHeightUsing needs to take flexbox stretched heights into account

third_party/WebKit/Source/core/layout/LayoutBox.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 3037 matching lines @@
 
     // We need to stop here, since we don't want to increase the height of the table
     // artificially.  We're going to rely on this cell getting expanded to some new
     // height, and then when we lay out again we'll use the calculation below.
     if (isTableCell() && (h.isAuto() || h.hasPercent())) {
         if (hasOverrideLogicalContentHeight())
             return overrideLogicalContentHeight();
         return logicalHeight() - borderAndPaddingLogicalHeight();
     }
 
+    if (isFlexItem()) {
+        LayoutFlexibleBox& flexBox = toLayoutFlexibleBox(*parent());
+        LayoutUnit stretchedHeight = flexBox.childLogicalHeightForPercentageResolution(*this);
+        if (stretchedHeight != LayoutUnit(-1))
+            return stretchedHeight;
+    }
+
     if (h.hasPercent() && isOutOfFlowPositioned()) {
         // FIXME: This is wrong if the containingBlock has a perpendicular writing mode.
         LayoutUnit availableHeight = containingBlockLogicalHeightForPositioned(containingBlock());
         return adjustContentBoxLogicalHeightForBoxSizing(valueForLength(h, availableHeight));
     }
 
     // FIXME: Should we pass intrinsicContentLogicalHeight() instead of -1 here?
     LayoutUnit heightIncludingScrollbar = computeContentAndScrollbarLogicalHeightUsing(MainOrPreferredSize, h, LayoutUnit(-1));
     if (heightIncludingScrollbar != -1)
         return std::max(LayoutUnit(), adjustContentBoxLogicalHeightForBoxSizing(heightIncludingScrollbar) - scrollbarLogicalHeight());
@@ skipping 1746 matching lines @@
         m_rareData->m_snapAreas->remove(&snapArea);
     }
 }
 
 SnapAreaSet* LayoutBox::snapAreas() const
 {
     return m_rareData ? m_rareData->m_snapAreas.get() : nullptr;
 }
 
 } // namespace blink