Remove NOTIFICATION_EXTENSION_ENABLED.

extensions/browser/extension_registry.cc

 // Copyright 2013 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.
 
 #include "extensions/browser/extension_registry.h"
 
 #include "base/strings/string_util.h"
 #include "extensions/browser/extension_registry_factory.h"
 #include "extensions/browser/extension_registry_observer.h"
 
@@ skipping 44 matching lines @@
     observer.OnExtensionLoaded(browser_context_, extension);
 }
 
 void ExtensionRegistry::TriggerOnReady(const Extension* extension) {
   CHECK(extension);
   DCHECK(enabled_extensions_.Contains(extension->id()));
   for (auto& observer : observers_)
     observer.OnExtensionReady(browser_context_, extension);
 }
 
+void ExtensionRegistry::TriggerOnEnabled(const Extension* extension) {
+  CHECK(extension);
+  DCHECK(enabled_extensions_.Contains(extension->id()));
+  for (auto& observer : observers_)
+    observer.OnExtensionEnabled(browser_context_, extension);
+}
+
 void ExtensionRegistry::TriggerOnUnloaded(const Extension* extension,
                                           UnloadedExtensionReason reason) {
   CHECK(extension);
   DCHECK(!enabled_extensions_.Contains(extension->id()));
   for (auto& observer : observers_)
     observer.OnExtensionUnloaded(browser_context_, extension, reason);
 }
 
 void ExtensionRegistry::TriggerOnWillBeInstalled(const Extension* extension,
                                                  bool is_update,
@@ skipping 127 matching lines @@
 }
 
 void ExtensionRegistry::Shutdown() {
   // Release references to all Extension objects in the sets.
   ClearAll();
   for (auto& observer : observers_)
     observer.OnShutdown(this);
 }
 
 }  // namespace extensions