Reduce calling count of UpdateAppState()

chrome/browser/ui/ash/launcher/browser_status_monitor.h

 // Copyright 2013 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_ASH_LAUNCHER_BROWSER_STATUS_MONITOR_H_
 #define CHROME_BROWSER_UI_ASH_LAUNCHER_BROWSER_STATUS_MONITOR_H_
 
 #include <map>
 #include <string>
 
 #include "ash/shelf/scoped_observer_with_duplicated_sources.h"
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/scoped_observer.h"
 #include "chrome/browser/ui/browser_list_observer.h"
 #include "chrome/browser/ui/tabs/tab_strip_model_observer.h"
+#include "content/public/browser/web_contents_observer.h"
 #include "ui/aura/client/activation_change_observer.h"
 #include "ui/aura/window_observer.h"
 #include "ui/gfx/display_observer.h"
 
 namespace aura {
 class Window;
 
 namespace client {
 class ActivationClient;
 }
@@ skipping 28 matching lines @@
   // gfx::DisplayObserver overrides:
   virtual void OnDisplayBoundsChanged(const gfx::Display& display) OVERRIDE;
   virtual void OnDisplayAdded(const gfx::Display& new_display) OVERRIDE;
   virtual void OnDisplayRemoved(const gfx::Display& old_display) OVERRIDE;
 
   // TabStripModelObserver overrides:
   virtual void ActiveTabChanged(content::WebContents* old_contents,
                                 content::WebContents* new_contents,
                                 int index,
                                 int reason) OVERRIDE;
+
   virtual void TabInsertedAt(content::WebContents* contents,
                              int index,
                              bool foreground) OVERRIDE;
-  virtual void TabDetachedAt(content::WebContents* contents,
-                             int index) OVERRIDE;
-  virtual void TabChangedAt(
-      content::WebContents* contents,
-      int index,
-      TabStripModelObserver::TabChangeType change_type) OVERRIDE;
-  virtual void TabReplacedAt(TabStripModel* tab_strip_model,
-                             content::WebContents* old_contents,
-                             content::WebContents* new_contents,
-                             int index) OVERRIDE;
 
- private:
-  typedef std::map<Browser*, std::string> BrowserToAppIDMap;
+  virtual void TabClosingAt(TabStripModel* tab_strip_mode,
+                            content::WebContents* contents,
+                            int index) OVERRIDE;
 
   // Update app state for |contents| and browser state.
   void UpdateAppAndBrowserState(content::WebContents* contents);
 
+ private:
+  // ActiveWebContentsObserver monitors active tab's WebContents to notify
+  // a navigation changing to BrowserStatusMonitor.

[Mr4D (OOO till 08-26), 2013/09/13 14:35:18]

This class monitors the WebContent of the active tab and notifies a navigation
to the BrowserStatusMonitor.

[simonhong_, 2013/09/15 17:27:08]

Done.

+  class ActiveWebContentsObserver : public content::WebContentsObserver {
+   public:
+    ActiveWebContentsObserver(content::WebContents* contents,
+                              BrowserStatusMonitor* monitor);
+    virtual ~ActiveWebContentsObserver();
+
+    // content::WebContentsObserver overrides:
+    virtual void NavigateToPendingEntry(
+      const GURL& url,
+      content::NavigationController::ReloadType reload_type) OVERRIDE;
+
+    virtual void DidNavigateMainFrame(
+        const content::LoadCommittedDetails& details,
+        const content::FrameNavigateParams& params) OVERRIDE;
+
+   private:
+    BrowserStatusMonitor* monitor_;
+
+    DISALLOW_COPY_AND_ASSIGN(ActiveWebContentsObserver);
+  };
+
+  typedef std::map<Browser*, std::string> BrowserToAppIDMap;
+  typedef std::map<content::WebContents*, ActiveWebContentsObserver*>
+      WebContentsToObserverMap;
+
   // A shortcut to call the BrowserShortcutLauncherItemController's
   // UpdateBrowserItemState().
   void UpdateBrowserItemState();
 
   ChromeLauncherController* launcher_controller_;
 
   // Hold all observed activation clients.
   ScopedObserverWithDuplicatedSources<aura::client::ActivationClient,
       aura::client::ActivationChangeObserver> observed_activation_clients_;
 
   // Hold all observed root windows.
   ScopedObserver<aura::Window, aura::WindowObserver> observed_root_windows_;
 
   BrowserToAppIDMap browser_to_app_id_map_;
 
+  WebContentsToObserverMap webcontents_to_observer_map_;
+
   DISALLOW_COPY_AND_ASSIGN(BrowserStatusMonitor);
 };
 
 #endif  // CHROME_BROWSER_UI_ASH_LAUNCHER_BROWSER_STATUS_MONITOR_H_