Allow assertions to be enabled in Blink Release builds.

Source/core/rendering/RenderBlock.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 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
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 235 matching lines @@
     virtual bool nodeAtPoint(const HitTestRequest&, HitTestResult&, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestAction) OVERRIDE;
 
     virtual void scrollbarsChanged(bool /*horizontalScrollbarChanged*/, bool /*verticalScrollbarChanged*/) { }
 
     LayoutUnit availableLogicalWidthForContent() const { return max<LayoutUnit>(0, logicalRightOffsetForContent() - logicalLeftOffsetForContent()); }
     LayoutUnit logicalLeftOffsetForContent() const { return isHorizontalWritingMode() ? borderLeft() + paddingLeft() : borderTop() + paddingTop(); }
     LayoutUnit logicalRightOffsetForContent() const { return logicalLeftOffsetForContent() + availableLogicalWidth(); }
     LayoutUnit startOffsetForContent() const { return style()->isLeftToRightDirection() ? logicalLeftOffsetForContent() : logicalWidth() - logicalRightOffsetForContent(); }
     LayoutUnit endOffsetForContent() const { return !style()->isLeftToRightDirection() ? logicalLeftOffsetForContent() : logicalWidth() - logicalRightOffsetForContent(); }
 
+#if ENABLE(ASSERT)
+    void checkPositionedObjectsNeedLayout();
+#endif
 #ifndef NDEBUG
-    void checkPositionedObjectsNeedLayout();
     void showLineTreeAndMark(const InlineBox* = 0, const char* = 0, const InlineBox* = 0, const char* = 0, const RenderObject* = 0) const;
 #endif
 
     // inline-block elements paint all phases atomically. This function ensures that. Certain other elements
     // (grid items, flex items) require this behavior as well, and this function exists as a helper for them.
     // It is expected that the caller will call this function independent of the value of paintInfo.phase.
     static void paintAsInlineBlock(RenderObject*, PaintInfo&, const LayoutPoint&);
 
     bool recalcChildOverflowAfterStyleChange();
     bool recalcOverflowAfterStyleChange();
@@ skipping 271 matching lines @@
     // FIXME: This is temporary as we move code that accesses block flow
     // member variables out of RenderBlock and into RenderBlockFlow.
     friend class RenderBlockFlow;
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderBlock, isRenderBlock());
 
 } // namespace WebCore
 
 #endif // RenderBlock_h