Add overflow:auto scrollbars to child flex basis.

Source/core/layout/LayoutFlexibleBox.cpp

Index: Source/core/layout/LayoutFlexibleBox.cpp
diff --git a/Source/core/layout/LayoutFlexibleBox.cpp b/Source/core/layout/LayoutFlexibleBox.cpp
index e1f9fede5c8486e6d1330b4978243dbf0ff78813..2f0d0d2d171db9215ecccdb272cfb77ee1168e33 100644
--- a/Source/core/layout/LayoutFlexibleBox.cpp
+++ b/Source/core/layout/LayoutFlexibleBox.cpp
@@ -411,8 +411,8 @@ LayoutUnit LayoutFlexibleBox::computeMainAxisExtentForChild(LayoutBox& child, Si
     // Otherwise we need the logical height.
     if (isHorizontalFlow() != child.styleRef().isHorizontalWritingMode()) {
         // We don't have to check for "auto" here - computeContentLogicalHeight will just return -1 for that case anyway.
-        if (size.isIntrinsic())
-            child.layoutIfNeeded();
+        // It's safe to access scrollbarLogicalHeight here because computeNextFlexLine will have already
+        // forced layout on the child.
         return child.computeContentLogicalHeight(sizeType, size, child.logicalHeight() - child.borderAndPaddingLogicalHeight()) + child.scrollbarLogicalHeight();
     }
     return child.computeLogicalWidthUsing(sizeType, size, contentLogicalWidth(), this) - child.borderAndPaddingLogicalWidth();
@@ -605,7 +605,8 @@ bool LayoutFlexibleBox::mainAxisLengthIsDefinite(LayoutBox& child, const Length&
 
 bool LayoutFlexibleBox::childFlexBaseSizeRequiresLayout(LayoutBox& child) const
 {
-    return !mainAxisLengthIsDefinite(child, flexBasisForChild(child)) && hasOrthogonalFlow(child);
+    return !mainAxisLengthIsDefinite(child, flexBasisForChild(child)) && (
+        hasOrthogonalFlow(child) || crossAxisOverflowForChild(child) == OAUTO);
 }
 
 LayoutUnit LayoutFlexibleBox::computeInnerFlexBaseSizeForChild(LayoutBox& child, ChildLayoutType childLayoutType)
@@ -618,14 +619,14 @@ LayoutUnit LayoutFlexibleBox::computeInnerFlexBaseSizeForChild(LayoutBox& child,
     Length flexBasis = flexBasisForChild(child);
     if (!mainAxisLengthIsDefinite(child, flexBasis)) {
         LayoutUnit mainAxisExtent;
-        if (hasOrthogonalFlow(child)) {
+        if (childFlexBaseSizeRequiresLayout(child)) {
             if (childLayoutType == NeverLayout)
                 return LayoutUnit();
 
             if (child.needsLayout() || childLayoutType == ForceLayout || !m_intrinsicSizeAlongMainAxis.contains(&child)) {
                 m_intrinsicSizeAlongMainAxis.remove(&child);
                 child.forceChildLayout();
-                m_intrinsicSizeAlongMainAxis.set(&child, child.logicalHeight());
+                m_intrinsicSizeAlongMainAxis.set(&child, hasOrthogonalFlow(child) ? child.logicalHeight() : child.logicalWidth());
             }
             mainAxisExtent = m_intrinsicSizeAlongMainAxis.get(&child);
         } else {
@@ -898,6 +899,18 @@ bool LayoutFlexibleBox::computeNextFlexLine(OrderedFlexItemList& orderedChildren
             continue;
         }
 
+        // If this condition is true, then computeMainAxisExtentForChild will call

[leviw_travelin_and_unemployed, 2015/08/20 18:53:06]

Extract into a named function?

[szager1, 2015/08/20 21:53:29]

Done.

+        // child.contentLogicalHeight() and child.scrollbarLogicalHeight(), so...
+        if (isHorizontalFlow() != child->styleRef().isHorizontalWritingMode()) {
+            // ... if the child has intrinsic min/max/preferred size, run layout on it now to make
+            // sure its logical height and scroll bars are up-to-date.
+            Length childFlexBasis = flexBasisForChild(*child);
+            Length childMinSize = isHorizontalFlow() ? child->style()->minWidth() : child->style()->minHeight();
+            Length childMaxSize = isHorizontalFlow() ? child->style()->maxWidth() : child->style()->maxHeight();
+            if (childFlexBasis.isIntrinsic() || childMinSize.isIntrinsic() || childMaxSize.isIntrinsic())
+                child->layoutIfNeeded();
+        }
+
         LayoutUnit childInnerFlexBaseSize = computeInnerFlexBaseSizeForChild(*child, relayoutChildren ? ForceLayout : LayoutIfNeeded);
         LayoutUnit childMainAxisMarginBorderPadding = mainAxisBorderAndPaddingExtentForChild(*child)
             + (isHorizontalFlow() ? child->marginWidth() : child->marginHeight());
@@ -1102,6 +1115,12 @@ EOverflow LayoutFlexibleBox::mainAxisOverflowForChild(LayoutBox& child) const
     return child.styleRef().overflowY();
 }
 
+EOverflow LayoutFlexibleBox::crossAxisOverflowForChild(LayoutBox& child) const
+{
+    if (isHorizontalFlow())
+        return child.styleRef().overflowY();
+    return child.styleRef().overflowX();
+}
 void LayoutFlexibleBox::layoutAndPlaceChildren(LayoutUnit& crossAxisOffset, const OrderedFlexItemList& children, const Vector<LayoutUnit, 16>& childSizes, LayoutUnit availableFreeSpace, bool relayoutChildren, SubtreeLayoutScope& layoutScope, Vector<LineContext>& lineContexts)
 {
     ASSERT(childSizes.size() == children.size());