[Pinch-to-zoom] Moved scale factor into PinchViewport

Source/core/frame/FrameHost.cpp

 /*
  * Copyright (C) 2013 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 26 matching lines @@
 
 namespace WebCore {
 
 PassOwnPtr<FrameHost> FrameHost::create(Page& page)
 {
     return adoptPtr(new FrameHost(page));
 }
 
 FrameHost::FrameHost(Page& page)
     : m_page(page)
-    , m_pinchViewport(*this)
+    , m_pinchViewport(adoptPtr(new PinchViewport(*this)))
 {
 }
 
 // Explicitly in the .cpp to avoid default constructor in .h
 FrameHost::~FrameHost()
 {
 }
 
 Settings& FrameHost::settings() const
 {
     return m_page.settings();
 }
 
 Chrome& FrameHost::chrome() const
 {
     return m_page.chrome();
 }
 
 UseCounter& FrameHost::useCounter() const
 {
     return m_page.useCounter();
 }
 
 float FrameHost::deviceScaleFactor() const
 {
     return m_page.deviceScaleFactor();
 }
 
-PinchViewport& FrameHost::pinchViewport()
+PinchViewport& FrameHost::pinchViewport() const
 {
-    return m_pinchViewport;
+    return *m_pinchViewport;
 }
 
 }