Oilpan: Move ChromeClient classes into Oilpan heap.

Source/core/layout/LayoutTestHelper.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef LayoutTestHelper_h
 #define LayoutTestHelper_h
 
 #include "core/dom/Document.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/Settings.h"
@@ skipping 16 matching lines @@
         document().view()->updateAllLifecyclePhases();
     }
 
     void enableCompositing()
     {
         m_pageHolder->page().settings().setAcceleratedCompositingEnabled(true);
         document().view()->updateAllLifecyclePhases();
     }
 
 private:
-    Page::PageClients m_pageClients;
     OwnPtr<DummyPageHolder> m_pageHolder;
 };
 
 } // namespace blink
 
 #endif // LayoutTestHelper_h