Use mocked scrollbar in webkit unit tests

third_party/WebKit/Source/web/tests/ScrollingCoordinatorTest.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 90 matching lines @@
 
 private:
     static void configureSettings(WebSettings* settings)
     {
         settings->setJavaScriptEnabled(true);
         settings->setAcceleratedCompositingEnabled(true);
         settings->setPreferCompositingToLCDTextEnabled(true);
     }
 
     FrameTestHelpers::WebViewHelper m_helper;
+    FrameTestHelpers::UseMockScrollbarSettings m_mockScrollbarSettings;
 };
 
 TEST_F(ScrollingCoordinatorTest, fastScrollingByDefault)
 {
     navigateTo("about:blank");
     forceFullCompositingUpdate();
 
     // Make sure the scrolling coordinator is active.
     FrameView* frameView = frame()->view();
     Page* page = frame()->page();
@@ skipping 479 matching lines @@
     EXPECT_FALSE(scrollLayer->shouldScrollOnMainThread());
 
     fixedPos->setInlineStyleProperty(CSSPropertyTransform, CSSValueNone);
     forceFullCompositingUpdate();
 
     EXPECT_FALSE(static_cast<LayoutBoxModelObject*>(fixedPos->layoutObject())->layer()->hasCompositedLayerMapping());
     EXPECT_TRUE(scrollLayer->shouldScrollOnMainThread());
 }
 
 } // namespace blink