Add setting for disabling compositor touch hit testing

Source/core/page/scrolling/ScrollingCoordinator.cpp

 /*
  * Copyright (C) 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 87 matching lines @@
     for (ScrollbarMap::iterator it = m_horizontalScrollbars.begin(); it != m_horizontalScrollbars.end(); ++it)
         GraphicsLayer::unregisterContentsLayer(it->value->layer());
     for (ScrollbarMap::iterator it = m_verticalScrollbars.begin(); it != m_verticalScrollbars.end(); ++it)
         GraphicsLayer::unregisterContentsLayer(it->value->layer());
 
 }
 
 bool ScrollingCoordinator::touchHitTestingEnabled() const
 {
     RenderView* contentRenderer = m_page->mainFrame()->contentRenderer();
-    return RuntimeEnabledFeatures::touchEnabled() && contentRenderer && contentRenderer->usesCompositing();
+    Settings* settings = m_page->mainFrame()->document()->settings();
+    return RuntimeEnabledFeatures::touchEnabled() && settings->compositorTouchHitTesting() && contentRenderer && contentRenderer->usesCompositing();
 }
 
 void ScrollingCoordinator::setShouldHandleScrollGestureOnMainThreadRegion(const Region& region)
 {
     if (WebLayer* scrollLayer = scrollingWebLayerForScrollableArea(m_page->mainFrame()->view())) {
         Vector<IntRect> rects = region.rects();
         WebVector<WebRect> webRects(rects.size());
         for (size_t i = 0; i < rects.size(); ++i)
             webRects[i] = rects[i];
         scrollLayer->setNonFastScrollableRegion(webRects);
@@ skipping 736 matching lines @@
         stringBuilder.resize(stringBuilder.length() - 2);
     return stringBuilder.toString();
 }
 
 String ScrollingCoordinator::mainThreadScrollingReasonsAsText() const
 {
     return mainThreadScrollingReasonsAsText(mainThreadScrollingReasons());
 }
 
 } // namespace WebCore