Move guest lifetime management to chrome

chrome/browser/guest_view/ad_view/ad_view_guest.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 CHROME_BROWSER_GUEST_VIEW_AD_VIEW_AD_VIEW_GUEST_H_
 #define CHROME_BROWSER_GUEST_VIEW_AD_VIEW_AD_VIEW_GUEST_H_
 
 #include "base/values.h"
 #include "chrome/browser/guest_view/guest_view.h"
-#include "content/public/browser/web_contents_observer.h"
 
-// An AdViewGuest is a WebContentsObserver on the guest WebContents of a
-// <adview> tag. It provides the browser-side implementation of the <adview>
-// API and manages the lifetime of <adview> extension events. AdViewGuest is
-// created on attachment. When a guest WebContents is associated with
-// a particular embedder WebContents, we call this "attachment".
+// An AdViewGuest provides the browser-side implementation of the <adview> API
+// and manages the dispatch of <adview> extension events. AdViewGuest is created
+// on attachment. When a guest WebContents is associated with a particular
+// embedder WebContents, we call this "attachment".
 // TODO(fsamuel): There might be an opportunity here to refactor and reuse code
 // between AdViewGuest and WebViewGuest.
-class AdViewGuest : public GuestView<AdViewGuest>,
-                    public content::WebContentsObserver {
+class AdViewGuest : public GuestView<AdViewGuest> {
  public:
   AdViewGuest(int guest_instance_id,
               content::WebContents* guest_web_contents,
               const std::string& extension_id);
 
   static const char Type[];
 
  private:
   virtual ~AdViewGuest();
 
@@ skipping 10 matching lines @@
       bool is_main_frame,
       const GURL& validated_url,
       int error_code,
       const base::string16& error_description,
       content::RenderViewHost* render_view_host) OVERRIDE;
 
   DISALLOW_COPY_AND_ASSIGN(AdViewGuest);
 };
 
 #endif  // CHROME_BROWSER_GUEST_VIEW_AD_VIEW_AD_VIEW_GUEST_H_