Remove the forceCompositingMode setting.

Source/web/tests/ScrollingCoordinatorChromiumTest.cpp

 /*
  * Copyright (C) 2012 Google 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 80 matching lines @@
     LocalFrame* frame() const { return m_helper.webViewImpl()->mainFrameImpl()->frame(); }
 
 protected:
     std::string m_baseURL;
     FrameTestHelpers::TestWebViewClient m_mockWebViewClient;
 
 private:
     static void configureSettings(WebSettings* settings)
     {
         settings->setJavaScriptEnabled(true);
-        settings->setForceCompositingMode(true);
         settings->setAcceleratedCompositingEnabled(true);
         settings->setAcceleratedCompositingForFixedPositionEnabled(true);
         settings->setAcceleratedCompositingForOverflowScrollEnabled(true);
         settings->setCompositedScrollingForFramesEnabled(true);
     }
 
     FrameTestHelpers::WebViewHelper m_helper;
 };
 
 TEST_F(ScrollingCoordinatorChromiumTest, fastScrollingByDefault)
@@ skipping 340 matching lines @@
 TEST_F(ScrollingCoordinatorChromiumTest, setupScrollbarLayerShouldNotCrash)
 {
     registerMockedHttpURLLoad("setup_scrollbar_layer_crash.html");
     navigateTo(m_baseURL + "setup_scrollbar_layer_crash.html");
     forceFullCompositingUpdate();
     // This test document setup an iframe with scrollbars, then switch to
     // an empty document by javascript.
 }
 
 } // namespace