Allow assertions to be enabled in Blink Release builds.

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 6eeb586350aeb0f860b1f88af5f715acbc2bee0e..dd0755c02ce54e685e39ab9cce09f283603f2666 100644
--- a/Source/core/rendering/RenderGrid.cpp
+++ b/Source/core/rendering/RenderGrid.cpp
@@ -744,7 +744,7 @@ void RenderGrid::distributeSpaceToTracks(Vector<GridTrack*>& tracks, Vector<Grid
     }
 }
 
-#ifndef NDEBUG
+#if ENABLE(ASSERT)
 bool RenderGrid::tracksAreWiderThanMinTrackBreadth(GridTrackSizingDirection direction, const Vector<GridTrack>& tracks)
 {
     for (size_t i = 0; i < tracks.size(); ++i) {
@@ -1020,7 +1020,7 @@ void RenderGrid::layoutGridItems()
         // now, just size as if we were a regular child.
         child->layoutIfNeeded();
 
-#ifndef NDEBUG
+#if ENABLE(ASSERT)
         const GridCoordinate& coordinate = cachedGridCoordinate(child);
         ASSERT(coordinate.columns.resolvedInitialPosition.toInt() < sizingData.columnTracks.size());
         ASSERT(coordinate.rows.resolvedInitialPosition.toInt() < sizingData.rowTracks.size());