Change HungPluginTabHelper to listen for infobar changes through Observer style.

chrome/browser/ui/hung_plugin_tab_helper.h

 // Copyright (c) 2012 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_UI_HUNG_PLUGIN_TAB_HELPER_H_
 #define CHROME_BROWSER_UI_HUNG_PLUGIN_TAB_HELPER_H_
 
 #include <map>
 
 #include "base/memory/linked_ptr.h"
 #include "base/strings/string16.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
-#include "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
+#include "components/infobars/core/infobar_manager.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
 
 namespace base {
 class FilePath;
 }
 
 namespace infobars {
 class InfoBarDelegate;
 }
 
 // Manages per-tab state with regard to hung plugins. This only handles
 // Pepper plugins which we know are windowless. Hung NPAPI plugins (which
 // may have native windows) can not be handled with infobars and have a
 // separate OS-specific hang monitoring.
 //
 // Our job is:
 // - Pop up an infobar when a plugin is hung.
 // - Terminate the plugin process if the user so chooses.
 // - Periodically re-show the hung plugin infobar if the user closes it without
 //   terminating the plugin.
 // - Hide the infobar if the plugin starts responding again.
 // - Keep track of all of this for any number of plugins.
 class HungPluginTabHelper
-    : public content::WebContentsObserver,
-      public content::NotificationObserver,
+    : public infobars::InfoBarManager::Observer,
+      public content::WebContentsObserver,
       public content::WebContentsUserData<HungPluginTabHelper> {
  public:
   virtual ~HungPluginTabHelper();
 
   // content::WebContentsObserver:
   virtual void PluginCrashed(const base::FilePath& plugin_path,
                              base::ProcessId plugin_pid) OVERRIDE;
   virtual void PluginHungStatusChanged(int plugin_child_id,
                                        const base::FilePath& plugin_path,
                                        bool is_hung) OVERRIDE;
 
-  // content::NotificationObserver:
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
-
   // Called by an infobar when the user selects to kill the plugin.
   void KillPlugin(int child_id);
 
  private:
   friend class content::WebContentsUserData<HungPluginTabHelper>;
 
   struct PluginState;
   typedef std::map<int, linked_ptr<PluginState> > PluginStateMap;
 
   explicit HungPluginTabHelper(content::WebContents* contents);
 
   // Called on a timer for a hung plugin to re-show the bar.
   void OnReshowTimer(int child_id);
 
   // Shows the bar for the plugin identified by the given state, updating the
   // state accordingly. The plugin must not have an infobar already.
   void ShowBar(int child_id, PluginState* state);
 
   // Closes the infobar associated with the given state. Note that this can
   // be called even if the bar is not opened, in which case it will do nothing.
   void CloseBar(PluginState* state);
 
-  content::NotificationRegistrar registrar_;
+  // infobars::InfoBarManager::Observer:
+  virtual void OnInfoBarRemoved(infobars::InfoBar* infobar,
+                                bool animate) OVERRIDE;
+  virtual void OnManagerShuttingDown(
+      infobars::InfoBarManager* manager) OVERRIDE;
+
+  bool observer_installed_;
 
   // All currently hung plugins.
   PluginStateMap hung_plugins_;
 
   DISALLOW_COPY_AND_ASSIGN(HungPluginTabHelper);
 };
 
 #endif  // CHROME_BROWSER_UI_HUNG_PLUGIN_TAB_HELPER_H_