Switch PluginObserver to use WebContentsUserData.

chrome/browser/plugins/plugin_observer.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_PLUGINS_PLUGIN_OBSERVER_H_
 #define CHROME_BROWSER_PLUGINS_PLUGIN_OBSERVER_H_
 
 #include "base/memory/weak_ptr.h"
+#include "chrome/browser/tab_contents/web_contents_user_data.h"
 #include "content/public/browser/web_contents_observer.h"
 
 #if defined(ENABLE_PLUGIN_INSTALLATION)
 #include <map>
 #endif
 
 class GURL;
 class InfoBarDelegate;
 class PluginFinder;
-class TabContents;
 
 #if defined(ENABLE_PLUGIN_INSTALLATION)
 class PluginInstaller;
 class PluginPlaceholderHost;
 #endif
 
-class PluginObserver : public content::WebContentsObserver {
+namespace content {
+class WebContents;
+}
+
+class PluginObserver : public content::WebContentsObserver,
+                       public WebContentsUserData<PluginObserver> {
  public:
-  explicit PluginObserver(TabContents* tab_contents);
   virtual ~PluginObserver();
 
   // content::WebContentsObserver implementation.
   virtual void PluginCrashed(const FilePath& plugin_path) OVERRIDE;
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
 
 #if defined(ENABLE_PLUGIN_INSTALLATION)
   void InstallMissingPlugin(PluginInstaller* installer);
 #endif
 
-  TabContents* tab_contents() { return tab_contents_; }
+  // Make public the web_contents() accessor that is protected in the parent.
+  using content::WebContentsObserver::web_contents;
 
  private:
+  explicit PluginObserver(content::WebContents* web_contents);
+  static int kUserDataKey;
+  friend class WebContentsUserData<PluginObserver>;
+
   class PluginPlaceholderHost;
 
   void OnBlockedUnauthorizedPlugin(const string16& name,
                                    const std::string& identifier);
   void OnBlockedOutdatedPlugin(int placeholder_id,
                                const std::string& identifier);
 #if defined(ENABLE_PLUGIN_INSTALLATION)
   void OnFindMissingPlugin(int placeholder_id, const std::string& mime_type);
 
   void FindMissingPlugin(int placeholder_id,
                          const std::string& mime_type,
                          PluginFinder* plugin_finder);
   void FindPluginToUpdate(int placeholder_id,
                           const std::string& identifier,
                           PluginFinder* plugin_finder);
   void OnRemovePluginPlaceholderHost(int placeholder_id);
 #endif
   void OnOpenAboutPlugins();
   void OnCouldNotLoadPlugin(const FilePath& plugin_path);
 
   base::WeakPtrFactory<PluginObserver> weak_ptr_factory_;
 
-  TabContents* tab_contents_;
-
 #if defined(ENABLE_PLUGIN_INSTALLATION)
   // Stores all PluginPlaceholderHosts, keyed by their routing ID.
   std::map<int, PluginPlaceholderHost*> plugin_placeholders_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(PluginObserver);
 };
 
 #endif  // CHROME_BROWSER_PLUGINS_PLUGIN_OBSERVER_H_