Remove EPM:all_hosts_ and use all_extension_views_ instead.

chrome/browser/renderer_host/chrome_render_view_host_observer.h

 // 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.
 
 #ifndef CHROME_BROWSER_RENDERER_HOST_CHROME_RENDER_VIEW_HOST_OBSERVER_H_
 #define CHROME_BROWSER_RENDERER_HOST_CHROME_RENDER_VIEW_HOST_OBSERVER_H_
 #pragma once
 
 #include "content/public/browser/render_view_host_observer.h"
 
 namespace chrome_browser_net {
 class Predictor;
 }
 
+namespace content {
+class WebContents;
+}
+
 class Extension;
 class Profile;
 
 // This class holds the Chrome specific parts of RenderViewHost, and has the
 // same lifetime.
 class ChromeRenderViewHostObserver : public content::RenderViewHostObserver {
  public:
   ChromeRenderViewHostObserver(content::RenderViewHost* render_view_host,
                                chrome_browser_net::Predictor* predictor);
   virtual ~ChromeRenderViewHostObserver();
 
   // content::RenderViewHostObserver overrides.
   virtual void RenderViewHostInitialized() OVERRIDE;
   virtual void RenderViewHostDestroyed(content::RenderViewHost* rvh) OVERRIDE;
   virtual void Navigate(const GURL& url) OVERRIDE;
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
 
  private:
    // Does extension-specific initialization when a new RenderViewHost is
    // created.
   void InitRenderViewHostForExtensions();
    // Does extension-specific initialization when a new renderer process is
    // created by a RenderViewHost.
   void InitRenderViewForExtensions();
   // Gets the extension or app (if any) that is associated with the RVH.
   const Extension* GetExtension();
   // Cleans up when a RenderViewHost is removed, or on destruction.
   void RemoveRenderViewHostForExtensions(content::RenderViewHost* rvh);
+  // Retrieves the WebContents for a RenderViewHost.
+  content::WebContents* GetWebContents(content::RenderViewHost* rvh);
   void OnFocusedEditableNodeTouched();
 
   Profile* profile_;
   chrome_browser_net::Predictor* predictor_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeRenderViewHostObserver);
 };
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_CHROME_RENDER_VIEW_HOST_OBSERVER_H_