Adds DevTools commands for forced viewport override.

third_party/WebKit/Source/web/ChromeClientImpl.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  *
  * 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.
@@ skipping 588 matching lines @@
 
     WebLocalFrameImpl* webframe = WebLocalFrameImpl::fromFrame(frame);
     webframe->didChangeContentsSize(size);
 }
 
 void ChromeClientImpl::pageScaleFactorChanged() const
 {
     m_webView->pageScaleFactorChanged();
 }
 
+void ChromeClientImpl::mainFrameScrollOffsetChanged() const
+{
+    m_webView->mainFrameScrollOffsetChanged();
+}
+
 float ChromeClientImpl::clampPageScaleFactorToLimits(float scale) const
 {
     return m_webView->clampPageScaleFactorToLimits(scale);
 }
 
 void ChromeClientImpl::layoutUpdated(LocalFrame* frame) const
 {
     m_webView->layoutUpdated(WebLocalFrameImpl::fromFrame(frame));
 }
 
@@ skipping 475 matching lines @@
 {
     return wrapUnique(m_webView->scheduler()->createFrameScheduler(blameContext).release());
 }
 
 double ChromeClientImpl::lastFrameTimeMonotonic() const
 {
     return m_webView->lastFrameTimeMonotonic();
 }
 
 } // namespace blink