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

chrome/browser/extensions/extension_webnavigation_api.h

Index: chrome/browser/extensions/extension_webnavigation_api.h
diff --git a/chrome/browser/extensions/extension_webnavigation_api.h b/chrome/browser/extensions/extension_webnavigation_api.h
index 9f475dc1ea3dc3c1d8aa76ab0fa3e038d6060eee..a00e5c6b02ee55d033a0aac0d450cdc159e720db 100644
--- a/chrome/browser/extensions/extension_webnavigation_api.h
+++ b/chrome/browser/extensions/extension_webnavigation_api.h
@@ -12,7 +12,6 @@
 
 #include <map>
 
-#include "base/memory/singleton.h"
 #include "chrome/browser/extensions/extension_function.h"
 #include "content/browser/tab_contents/tab_contents_observer.h"
 #include "content/common/notification_observer.h"
@@ -132,19 +131,12 @@ class ExtensionWebNavigationTabObserver : public TabContentsObserver {
 // system.
 class ExtensionWebNavigationEventRouter : public NotificationObserver {
  public:
-  // Returns the singleton instance of the event router.
-  static ExtensionWebNavigationEventRouter* GetInstance();
+  explicit ExtensionWebNavigationEventRouter() {}
+  virtual ~ExtensionWebNavigationEventRouter() {}

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

same inlining nit here

 
-  // Invoked by the extensions service once the extension system is fully set
-  // up and can start dispatching events to extensions.
   void Init();
 
  private:
-  friend struct DefaultSingletonTraits<ExtensionWebNavigationEventRouter>;
-
-  ExtensionWebNavigationEventRouter();
-  virtual ~ExtensionWebNavigationEventRouter();
-
   // NotificationObserver implementation.
   virtual void Observe(NotificationType type,
                        const NotificationSource& source,