[CSS Grid Layout] Handling overflow on Content Alignment properties.

Source/core/rendering/RenderGrid.h

 /*
  * Copyright (C) 2011 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 106 matching lines @@
     LayoutUnit startOfColumnForChild(const RenderBox& child) const;
     LayoutUnit endOfColumnForChild(const RenderBox& child) const;
     LayoutUnit columnPositionLeft(const RenderBox&) const;
     LayoutUnit columnPositionRight(const RenderBox&) const;
     LayoutUnit centeredColumnPositionForChild(const RenderBox&) const;
     LayoutUnit columnPositionForChild(const RenderBox&) const;
     LayoutUnit startOfRowForChild(const RenderBox& child) const;
     LayoutUnit endOfRowForChild(const RenderBox& child) const;
     LayoutUnit centeredRowPositionForChild(const RenderBox&) const;
     LayoutUnit rowPositionForChild(const RenderBox&) const;
-    LayoutUnit contentPositionAndDistributionColumnOffset(LayoutUnit availableFreeSpace, ContentPosition, ContentDistributionType, unsigned numberOfItems) const;
-    LayoutUnit contentPositionAndDistributionRowOffset(LayoutUnit availableFreeSpace, ContentPosition, ContentDistributionType, unsigned numberOfItems) const;
+    LayoutUnit contentPositionAndDistributionColumnOffset(LayoutUnit availableFreeSpace, ContentPosition, ContentDistributionType, OverflowAlignment, unsigned numberOfItems) const;
+    LayoutUnit contentPositionAndDistributionRowOffset(LayoutUnit availableFreeSpace, ContentPosition, ContentDistributionType, OverflowAlignment, unsigned numberOfItems) const;
     LayoutPoint findChildLogicalPosition(const RenderBox&, LayoutSize contentAlignmentOffset) const;
     GridCoordinate cachedGridCoordinate(const RenderBox&) const;
 
     LayoutUnit gridAreaBreadthForChild(const RenderBox& child, GridTrackSizingDirection, const Vector<GridTrack>&) const;
 
     virtual void paintChildren(const PaintInfo&, const LayoutPoint&) override;
     bool allowedToStretchLogicalHeightForChild(const RenderBox& child) const;
     bool needToStretchChildLogicalHeight(const RenderBox&) const;
     LayoutUnit childIntrinsicHeight(const RenderBox&) const;
     LayoutUnit childIntrinsicWidth(const RenderBox&) const;
@@ skipping 30 matching lines @@
     OrderIterator m_orderIterator;
     Vector<RenderBox*> m_gridItemsOverflowingGridArea;
     HashMap<const RenderBox*, size_t> m_gridItemsIndexesMap;
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderGrid, isRenderGrid());
 
 } // namespace blink
 
 #endif // RenderGrid_h