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

Source/core/layout/LayoutGrid.cpp

Index: Source/core/layout/LayoutGrid.cpp
diff --git a/Source/core/layout/LayoutGrid.cpp b/Source/core/layout/LayoutGrid.cpp
index 049a749f8df9c6d7b569a6f106863c2af03e1973..82177396dfbeb51ea03a28e2f4fc89f993cfd2f0 100644
--- a/Source/core/layout/LayoutGrid.cpp
+++ b/Source/core/layout/LayoutGrid.cpp
@@ -525,7 +525,7 @@ LayoutUnit LayoutGrid::computeUsedBreadthOfSpecifiedLength(GridTrackSizingDirect
 {
     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)