[css-grid] Percentage columns should remove scrollbar's width

Source/core/layout/LayoutGrid.cpp

 /*
  * 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 507 matching lines @@
     }
 
     ASSERT(trackLength.isMinContent() || trackLength.isAuto() || trackLength.isMaxContent());
     return infinity;
 }
 
 LayoutUnit LayoutGrid::computeUsedBreadthOfSpecifiedLength(GridTrackSizingDirection direction, const Length& trackLength) const
 {
     ASSERT(trackLength.isSpecified());
     // FIXME: The -1 here should be replaced by whatever the intrinsic height of the grid is.
-    return valueForLength(trackLength, direction == ForColumns ? logicalWidth() - borderAndPaddingLogicalWidth() : std::max(LayoutUnit(), computeContentLogicalHeight(MainOrPreferredSize, style()->logicalHeight(), -1)));
+    return valueForLength(trackLength, direction == ForColumns ? contentLogicalWidth() : std::max(LayoutUnit(), computeContentLogicalHeight(MainOrPreferredSize, style()->logicalHeight(), -1)));
 }
 
 static bool sortByGridNormalizedFlexValue(const GridTrackForNormalization& track1, const GridTrackForNormalization& track2)
 {
     return track1.m_normalizedFlexValue < track2.m_normalizedFlexValue;
 }
 
 double LayoutGrid::computeNormalizedFractionBreadth(Vector<GridTrack>& tracks, const GridSpan& tracksSpan, GridTrackSizingDirection direction, LayoutUnit spaceToFill) const
 {
     LayoutUnit allocatedSpace;
@@ skipping 1384 matching lines @@
 
     return LayoutPoint(rowAxisOffset, columnAxisOffsetForChild(child));
 }
 
 void LayoutGrid::paintChildren(const PaintInfo& paintInfo, const LayoutPoint& paintOffset)
 {
     GridPainter(*this).paintChildren(paintInfo, paintOffset);
 }
 
 } // namespace blink