Merge AcceleratedCompositingForOverflowScroll into PreferCompositingToLCDText.

Source/core/rendering/RenderLayerScrollableArea.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 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 1423 matching lines @@
         return false;
 
     // See https://codereview.chromium.org/176633003/ for the tests that fail without this disabler.
     DisableCompositingQueryAsserts disabler;
     return layer()->hasCompositedLayerMapping() && layer()->compositedLayerMapping()->scrollingLayer();
 }
 
 static bool layerNeedsCompositedScrolling(const RenderLayer* layer)
 {
     return layer->scrollsOverflow()
-        && layer->compositor()->acceleratedCompositingForOverflowScrollEnabled()
+        && layer->compositor()->preferCompositingToLCDTextEnabled()
         && !layer->hasDescendantWithClipPath()
         && !layer->hasAncestorWithClipPath();
 }
 
 void RenderLayerScrollableArea::updateNeedsCompositedScrolling()
 {
     const bool needsCompositedScrolling = layerNeedsCompositedScrolling(layer());
     if (static_cast<bool>(m_needsCompositedScrolling) != needsCompositedScrolling) {
         m_needsCompositedScrolling = needsCompositedScrolling;
         layer()->didUpdateNeedsCompositedScrolling();
     }
 }
 
 void RenderLayerScrollableArea::setTopmostScrollChild(RenderLayer* scrollChild)
 {
     // We only want to track the topmost scroll child for scrollable areas with
     // overlay scrollbars.
     if (!hasOverlayScrollbars())
         return;
     m_nextTopmostScrollChild = scrollChild;
 }
 
 } // namespace blink