Fix handling of 'inherit' and 'initial' for grid lines

Source/core/rendering/RenderGrid.cpp

Index: Source/core/rendering/RenderGrid.cpp
diff --git a/Source/core/rendering/RenderGrid.cpp b/Source/core/rendering/RenderGrid.cpp
index 16c1db770e36cd0acc478053d2b8351639d37966..be4f2e7f284bd1ee29584dc9cf9ff21a90411d08 100644
--- a/Source/core/rendering/RenderGrid.cpp
+++ b/Source/core/rendering/RenderGrid.cpp
@@ -719,9 +719,9 @@ RenderGrid::GridSpan RenderGrid::resolveGridPositionsFromAutoPlacementPosition(c
 
 PassOwnPtr<RenderGrid::GridSpan> RenderGrid::resolveGridPositionsFromStyle(const RenderBox* gridItem, TrackSizingDirection direction) const
 {
-    const GridPosition& initialPosition = (direction == ForColumns) ? gridItem->style()->gridItemStart() : gridItem->style()->gridItemBefore();
+    const GridPosition& initialPosition = (direction == ForColumns) ? gridItem->style()->gridStart() : gridItem->style()->gridBefore();
     const GridPositionSide initialPositionSide = (direction == ForColumns) ? StartSide : BeforeSide;
-    const GridPosition& finalPosition = (direction == ForColumns) ? gridItem->style()->gridItemEnd() : gridItem->style()->gridItemAfter();
+    const GridPosition& finalPosition = (direction == ForColumns) ? gridItem->style()->gridEnd() : gridItem->style()->gridAfter();
     const GridPositionSide finalPositionSide = (direction == ForColumns) ? EndSide : AfterSide;
 
     if (initialPosition.isAuto() && finalPosition.isAuto()) {