[uber page] Split up initialization of handlers from initialization of webui pages

chrome/browser/ui/webui/options/options_ui.h

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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_WEBUI_OPTIONS_OPTIONS_UI_H_
 #define CHROME_BROWSER_UI_WEBUI_OPTIONS_OPTIONS_UI_H_
 #pragma once
 
 #include <string>
 #include <vector>
 
@@ skipping 12 matching lines @@
  public:
   OptionsPageUIHandler();
   virtual ~OptionsPageUIHandler();
 
   // Is this handler enabled?
   virtual bool IsEnabled();
 
   // Collects localized strings for options page.
   virtual void GetLocalizedValues(base::DictionaryValue* localized_strings) = 0;
 
-  // Initialize the page.  Called once the DOM is available for manipulation.
-  // This will be called only once.
-  virtual void Initialize() {}
+  // Will be called only once in the life time of the handler. Generally used to
+  // add observers, initializes preferences, or start asynchronous calls from
+  // various services.
+  virtual void InitializeHandler() {}
+
+  // Initialize the page. Called once the DOM is available for manipulation.
+  // This will be called when a RenderView is re-used (when navigated to with
+  // back/forward or session restored in some cases) or when created.
+  virtual void InitializePage() {}
 
   // Uninitializes the page.  Called just before the object is destructed.
   virtual void Uninitialize() {}
 
   // WebUIMessageHandler implementation.
   virtual void RegisterMessages() OVERRIDE {}
 
   // content::NotificationObserver implementation.
   virtual void Observe(int type,
                        const content::NotificationSource& source,
@@ skipping 61 matching lines @@
   void SetCommandLineString(content::RenderViewHost* render_view_host);
 
   bool initialized_handlers_;
 
   std::vector<OptionsPageUIHandler*> handlers_;
 
   DISALLOW_COPY_AND_ASSIGN(OptionsUI);
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_OPTIONS_OPTIONS_UI_H_