Convert Settings::rootLayerScrolls to RuntimeEnabledFeatures

third_party/WebKit/Source/core/paint/PaintLayerClipper.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 223 matching lines @@
         backgroundRect.intersect(newPosClip);
         backgroundRect.setIsClippedByClipCss();
         foregroundRect.intersect(newPosClip);
         foregroundRect.setIsClippedByClipCss();
     }
 }
 
 void PaintLayerClipper::calculateClipRects(const ClipRectsContext& context, ClipRects& clipRects) const
 {
     const LayoutBoxModelObject& layoutObject = *m_layer.layoutObject();
-    bool rootLayerScrolls = layoutObject.document().settings() && layoutObject.document().settings()->rootLayerScrolls();
-    if (!m_layer.parent() && !rootLayerScrolls) {
+    if (!m_layer.parent() && !RuntimeEnabledFeatures::rootLayerScrollingEnabled()) {
         // The root layer's clip rect is always infinite.
         clipRects.reset(LayoutRect(LayoutRect::infiniteIntRect()));
         return;
     }
 
     bool isClippingRoot = &m_layer == context.rootLayer;
 
     // For transformed layers, the root layer was shifted to be us, so there is no need to
     // examine the parent. We want to cache clip rects with us as the root.
     PaintLayer* parentLayer = !isClippingRoot ? m_layer.parent() : nullptr;
@@ skipping 70 matching lines @@
 
 ClipRects& PaintLayerClipper::paintingClipRects(const PaintLayer* rootLayer, ShouldRespectOverflowClipType respectOverflowClip, const LayoutSize& subpixelAccumulation) const
 {
     ClipRectsContext context(rootLayer, PaintingClipRects, IgnoreOverlayScrollbarSize, subpixelAccumulation);
     if (respectOverflowClip == IgnoreOverflowClip)
         context.setIgnoreOverflowClip();
     return getClipRects(context);
 }
 
 } // namespace blink