Allow assertions to be enabled in Blink Release builds.

Source/core/rendering/RenderTableCell.h

 /*
  * Copyright (C) 1997 Martin Jones (mjones@kde.org)
  *           (C) 1997 Torben Weis (weis@kde.org)
  *           (C) 1998 Waldo Bastian (bastian@kde.org)
  *           (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2009, 2013 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 193 matching lines @@
         return style()->borderStart();
     }
 
     const BorderValue& borderAdjoiningCellAfter(const RenderTableCell* cell)
     {
         ASSERT_UNUSED(cell, table()->cellBefore(cell) == this);
         // FIXME: https://webkit.org/b/79272 - Add support for mixed directionality at the cell level.
         return style()->borderEnd();
     }
 
-#ifndef NDEBUG
+#if ENABLE(ASSERT)
     bool isFirstOrLastCellInRow() const
     {
         return !table()->cellAfter(this) || !table()->cellBefore(this);
     }
 #endif
 protected:
     virtual void styleDidChange(StyleDifference, const RenderStyle* oldStyle) OVERRIDE;
     virtual void computePreferredLogicalWidths() OVERRIDE;
 
     virtual void addLayerHitTestRects(LayerHitTestRects&, const RenderLayer* currentCompositedLayer, const LayoutPoint& layerOffset, const LayoutRect& containerRect) const OVERRIDE;
@@ skipping 87 matching lines @@
 
 inline RenderTableCell* RenderTableRow::lastCell() const
 {
     ASSERT(children() == virtualChildren());
     return toRenderTableCell(children()->lastChild());
 }
 
 } // namespace WebCore
 
 #endif // RenderTableCell_h