[CSS Grid Layout] Add support to place items using named grid lines

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 17 matching lines @@
 
 #include "core/rendering/OrderIterator.h"
 #include "core/rendering/RenderBlock.h"
 
 namespace WebCore {
 
 struct GridCoordinate;
 struct GridSpan;
 class GridTrack;
 
-enum GridTrackSizingDirection {
-    ForColumns,
-    ForRows
-};
+typedef HashMap<String, Vector<size_t> > NamedGridLinesMap;
 
 class RenderGrid FINAL : public RenderBlock {
 public:
     RenderGrid(Element*);
     virtual ~RenderGrid();
 
     virtual const char* renderName() const OVERRIDE;
 
     virtual void layoutBlock(bool relayoutChildren) OVERRIDE;
 
@@ skipping 94 matching lines @@
     {
         ASSERT(!gridIsDirty());
         return m_grid[0].size();
     }
     size_t gridRowCount() const
     {
         ASSERT(!gridIsDirty());
         return m_grid.size();
     }
 
+    const NamedGridLinesMap& gridLinesForSide(GridPositionSide side) const { return (side == ColumnStartSide || side == ColumnEndSide) ? m_namedGridColumnLines : m_namedGridRowLines; }
+    void createGridLineNamesMapsForDirection(GridTrackSizingDirection);
+
     typedef Vector<RenderBox*, 1> GridCell;
     typedef Vector<Vector<GridCell> > GridRepresentation;
     GridRepresentation m_grid;
     bool m_gridIsDirty;
     Vector<LayoutUnit> m_rowPositions;
     Vector<LayoutUnit> m_columnPositions;
     HashMap<const RenderBox*, GridCoordinate> m_gridItemCoordinate;
     OrderIterator m_orderIterator;
     Vector<RenderBox*> m_gridItemsOverflowingGridArea;
 
+    NamedGridLinesMap m_namedGridColumnLines;
+    NamedGridLinesMap m_namedGridRowLines;
+
     friend class GridCoordinateSorter;
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderGrid, isRenderGrid());
 
 } // namespace WebCore
 
 #endif // RenderGrid_h