Only return the visible page actions from PageActionController.

chrome/common/extensions/extension_action.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_COMMON_EXTENSIONS_EXTENSION_ACTION_H_
 #define CHROME_COMMON_EXTENSIONS_EXTENSION_ACTION_H_
 #pragma once
 
 #include <map>
 #include <string>
@@ skipping 23 matching lines @@
   enum Type {
     TYPE_NONE,
     TYPE_BROWSER,
     TYPE_PAGE,
   };
 
   explicit ExtensionAction(const std::string& extension_id);
   ~ExtensionAction();
 
   // extension id
-  std::string extension_id() const { return extension_id_; }
+  const std::string& extension_id() const { return extension_id_; }
 
   // action id -- only used with legacy page actions API
   std::string id() const { return id_; }
   void set_id(const std::string& id) { id_ = id; }
 
   // static icon paths from manifest -- only used with legacy page actions API.
   std::vector<std::string>* icon_paths() { return &icon_paths_; }
 
   // Set the url which the popup will load when the user clicks this action's
   // icon.  Setting an empty URL will disable the popup for a given tab.
@@ skipping 142 matching lines @@
 };
 
 template<>
 struct ExtensionAction::ValueTraits<int> {
   static int CreateEmpty() {
     return -1;
   }
 };
 
 #endif  // CHROME_COMMON_EXTENSIONS_EXTENSION_ACTION_H_