Improve extension icon prediction

chrome/browser/extensions/extension_action_manager.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_EXTENSIONS_EXTENSION_ACTION_MANAGER_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_ACTION_MANAGER_H_
 
 #include <map>
 #include <string>
 
@@ skipping 23 matching lines @@
 
   // Retrieves the page action, or browser action for |extension|.
   // If the result is not NULL, it remains valid until the extension is
   // unloaded.
   ExtensionAction* GetPageAction(const extensions::Extension& extension) const;
   ExtensionAction* GetBrowserAction(
       const extensions::Extension& extension) const;
   ExtensionAction* GetSystemIndicator(
       const extensions::Extension& extension) const;
 
+  // Gets the best fit ExtensionAction for the given |extension|.
+  // Excludes system indicators.
+  ExtensionAction* GetBestFitAction(
+      const extensions::Extension& extension) const;
+
  private:
   // Implement ExtensionRegistryObserver.
   virtual void OnExtensionUnloaded(content::BrowserContext* browser_context,
                                    const Extension* extension,
                                    UnloadedExtensionInfo::Reason reason)
       OVERRIDE;
 
   Profile* profile_;
 
   // Listen to extension unloaded notifications.
   ScopedObserver<ExtensionRegistry, ExtensionRegistryObserver>
       extension_registry_observer_;
 
   // Keyed by Extension ID.  These maps are populated lazily when their
   // ExtensionAction is first requested, and the entries are removed when the
   // extension is unloaded.  Not every extension has a page action or browser
   // action.
   typedef std::map<std::string, linked_ptr<ExtensionAction> > ExtIdToActionMap;
   mutable ExtIdToActionMap page_actions_;
   mutable ExtIdToActionMap browser_actions_;
   mutable ExtIdToActionMap system_indicators_;
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_ACTION_MANAGER_H_