Use ExtensionRegistryObserver instead of deprecated extension notification from autocomplete

chrome/browser/autocomplete/extension_app_provider.h

Index: chrome/browser/autocomplete/extension_app_provider.h
diff --git a/chrome/browser/autocomplete/extension_app_provider.h b/chrome/browser/autocomplete/extension_app_provider.h
index 5dbcc2638bb9259664955149f35bbe8642d5b234..6494551d876a0385fb89a1f7e50d3e734fdbd4bf 100644
--- a/chrome/browser/autocomplete/extension_app_provider.h
+++ b/chrome/browser/autocomplete/extension_app_provider.h
@@ -10,18 +10,25 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
+#include "base/scoped_observer.h"
 #include "chrome/browser/autocomplete/autocomplete_input.h"
 #include "chrome/browser/autocomplete/autocomplete_match.h"
 #include "chrome/browser/autocomplete/autocomplete_provider.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
+#include "extensions/browser/extension_registry_observer.h"
 #include "ui/base/window_open_disposition.h"
 
+namespace extensions {
+class ExtensionRegistry;
+}
+
 // This provider is responsible for keeping track of which Extension Apps are
 // installed and their URLs.  An instance of it gets created and managed by
 // AutocompleteController.
 class ExtensionAppProvider : public AutocompleteProvider,
-                             public content::NotificationObserver {
+                             public content::NotificationObserver,
+                             public extensions::ExtensionRegistryObserver {
  public:
   ExtensionAppProvider(AutocompleteProviderListener* listener,
                        Profile* profile);
@@ -81,8 +88,17 @@ class ExtensionAppProvider : public AutocompleteProvider,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE;
 
+  // extensions::ExtensionRegistryObserver implementation:
+  virtual void OnExtensionLoaded(
+      content::BrowserContext* browser_context,
+      const extensions::Extension* extension) OVERRIDE;
+
   content::NotificationRegistrar registrar_;
 
+  ScopedObserver<extensions::ExtensionRegistry,
+                 extensions::ExtensionRegistryObserver>
+      extension_registry_observer_;
+
   // Our cache of ExtensionApp objects (name + url) representing the extension
   // apps we know/care about.
   ExtensionApps extension_apps_;