Change event routers from singletons to being owned by the ExtensionService.

chrome/browser/extensions/extension_bookmarks_module.h

 // Copyright (c) 2011 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_BOOKMARKS_MODULE_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_BOOKMARKS_MODULE_H_
 #pragma once
 
 #include <list>
 #include <set>
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
-#include "base/memory/singleton.h"
 #include "chrome/browser/bookmarks/bookmark_model_observer.h"
 #include "chrome/browser/extensions/extension_function.h"
 #include "chrome/browser/ui/shell_dialogs.h"
 #include "content/common/notification_observer.h"
 #include "content/common/notification_registrar.h"
 
 class FilePath;
 
 // Observes BookmarkModel and then routes the notifications as events to
 // the extension system.
 class ExtensionBookmarkEventRouter : public BookmarkModelObserver {
  public:
-  static ExtensionBookmarkEventRouter* GetInstance();
-  virtual ~ExtensionBookmarkEventRouter();
+  explicit ExtensionBookmarkEventRouter() {}
+  virtual ~ExtensionBookmarkEventRouter() {}

[asargent_no_longer_on_chrome, 2011/05/24 18:18:00]

nit: probably shouldn't inline the constructor/destructor here. See "Stop
inlining constructors and destructors" section of:

http://dev.chromium.org/developers/coding-style/cpp-dos-and-donts

[Yoyo Zhou, 2011/05/24 19:17:55]

Done here and elsewhere.

 
-  // Call this for each model to observe.  Safe to call multiple times per
-  // model.
+  // Initialize to observe this bookmark model.
   void Observe(BookmarkModel* model);
 
   // BookmarkModelObserver:
   virtual void Loaded(BookmarkModel* model) OVERRIDE;
   virtual void BookmarkModelBeingDeleted(BookmarkModel* model) OVERRIDE {}
   virtual void BookmarkNodeMoved(BookmarkModel* model,
                                  const BookmarkNode* old_parent,
                                  int old_index,
                                  const BookmarkNode* new_parent,
                                  int new_index) OVERRIDE;
   virtual void BookmarkNodeAdded(BookmarkModel* model,
                                  const BookmarkNode* parent,
                                  int index) OVERRIDE;
   virtual void BookmarkNodeRemoved(BookmarkModel* model,
                                    const BookmarkNode* parent,
                                    int old_index,
                                    const BookmarkNode* node) OVERRIDE;
   virtual void BookmarkNodeChanged(BookmarkModel* model,
                                    const BookmarkNode* node) OVERRIDE;
   virtual void BookmarkNodeFaviconLoaded(BookmarkModel* model,
                                          const BookmarkNode* node) OVERRIDE;
   virtual void BookmarkNodeChildrenReordered(BookmarkModel* model,
                                              const BookmarkNode* node) OVERRIDE;
   virtual void BookmarkImportBeginning(BookmarkModel* model) OVERRIDE;
   virtual void BookmarkImportEnding(BookmarkModel* model) OVERRIDE;
 
  private:
-  ExtensionBookmarkEventRouter();
-  friend struct DefaultSingletonTraits<ExtensionBookmarkEventRouter>;
-
   // Helper to actually dispatch an event to extension listeners.
   void DispatchEvent(Profile* profile,
                      const char* event_name,
                      const std::string& json_args);
 
-  // These are stored so that Observe can be called multiple times safely.
-  // This way the caller doesn't have to know whether it's already observing
-  // a particular model or not.  The pointers are not owned by this object.
-  std::set<BookmarkModel*> models_;
+  // The model being observed.
+  BookmarkModel* model_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionBookmarkEventRouter);
 };
 
 class BookmarksFunction : public AsyncExtensionFunction,
                           public NotificationObserver {
  public:
   // AsyncExtensionFunction:
   virtual void Run() OVERRIDE;
 
@@ skipping 150 matching lines @@
   // BookmarkManagerIOFunction:
   virtual bool RunImpl() OVERRIDE;
   virtual void FileSelected(const FilePath& path, int index, void* params)
       OVERRIDE;
 
  private:
   DECLARE_EXTENSION_FUNCTION_NAME("bookmarks.export");
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_BOOKMARKS_MODULE_H_