Implement the Instant extended API startMargin, endMargin, and rtl properties and the onmarginchang…

content/public/renderer/render_view_observer.cc

 // Copyright (c) 2011 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.
 
 #include "content/public/renderer/render_view_observer.h"
 
 #include "content/renderer/render_view_impl.h"
 
 using WebKit::WebFrame;
 
@@ skipping 26 matching lines @@
 }
 
 bool RenderViewObserver::Send(IPC::Message* message) {
   if (render_view_)
     return render_view_->Send(message);
 
   delete message;
   return false;
 }
 
-RenderView* RenderViewObserver::render_view() {
+RenderView* RenderViewObserver::render_view() const {
   return render_view_;
 }
 
 void RenderViewObserver::RenderViewGone() {
   render_view_ = NULL;
 }
 
 }  // namespace content