Replace ENABLE(ASSERT) with DCHECK_IS_ON().

third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.h

 /*
  * Copyright (C) 2003, 2009, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 574 matching lines @@
   // LayoutObject to hold our custom resizer.
   LayoutScrollbarPart* m_resizer;
 
   ScrollAnchor m_scrollAnchor;
 
   std::unique_ptr<PaintLayerScrollableAreaRareData> m_rareData;
 
   // MainThreadScrollingReason due to the properties of the LayoutObject
   uint32_t m_reasons;
 
-#if ENABLE(ASSERT)
+#if DCHECK_IS_ON()
   bool m_hasBeenDisposed;
 #endif
 };
 
 DEFINE_TYPE_CASTS(PaintLayerScrollableArea,
                   ScrollableArea,
                   scrollableArea,
                   scrollableArea->isPaintLayerScrollableArea(),
                   scrollableArea.isPaintLayerScrollableArea());
 
 }  // namespace blink
 
 #endif  // LayerScrollableArea_h