[CSS Grid Layout] Avoid reset override logical width/height for non relative elements

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 add685ab608673b919360b1109411e75028b78bd..133368064420ad67b5d8e71e05704321da5cc8b5 100644
--- a/Source/core/layout/LayoutGrid.cpp
+++ b/Source/core/layout/LayoutGrid.cpp
@@ -617,15 +617,16 @@ LayoutUnit LayoutGrid::logicalHeightForChild(LayoutBox& child, Vector<GridTrack>
     SubtreeLayoutScope layoutScope(child);
     LayoutUnit oldOverrideContainingBlockContentLogicalWidth = child.hasOverrideContainingBlockLogicalWidth() ? child.overrideContainingBlockContentLogicalWidth() : LayoutUnit();
     LayoutUnit overrideContainingBlockContentLogicalWidth = gridAreaBreadthForChild(child, ForColumns, columnTracks);
-    if (child.style()->logicalHeight().isPercent() || oldOverrideContainingBlockContentLogicalWidth != overrideContainingBlockContentLogicalWidth)
+    if (child.hasRelativeLogicalHeight() || oldOverrideContainingBlockContentLogicalWidth != overrideContainingBlockContentLogicalWidth)
         layoutScope.setNeedsLayout(&child);
 
     child.clearOverrideLogicalContentHeight();
 
     child.setOverrideContainingBlockContentLogicalWidth(overrideContainingBlockContentLogicalWidth);
-    // If |child| has a percentage logical height, we shouldn't let it override its intrinsic height, which is
+    // If |child| has a relative logical height, we shouldn't let it override its intrinsic height, which is
     // what we are interested in here. Thus we need to set the override logical height to -1 (no possible resolution).
-    child.setOverrideContainingBlockContentLogicalHeight(-1);
+    if (child.hasRelativeLogicalHeight())
+        child.setOverrideContainingBlockContentLogicalHeight(-1);

[Manuel Rego, 2015/03/05 06:31:07]

Applied the same change to the new lines doing:
  child.setOverrideContainingBlockContentLogicalWidth(-1);

Which were introduced in:
https://codereview.chromium.org/914993003

     child.layoutIfNeeded();
     return child.logicalHeight() + child.marginLogicalHeight();
 }