Remove NOTIFICATION_EXTENSION_ENABLED.

extensions/browser/extension_registry.h

 // 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.
 
 #ifndef EXTENSIONS_BROWSER_EXTENSION_REGISTRY_H_
 #define EXTENSIONS_BROWSER_EXTENSION_REGISTRY_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/observer_list.h"
 #include "base/version.h"
 #include "components/keyed_service/core/keyed_service.h"
+#include "extensions/browser/events/lazy_event_dispatch_util.h"
 #include "extensions/browser/uninstall_reason.h"
 #include "extensions/common/extension_set.h"
 #include "extensions/features/features.h"
 
 #if !BUILDFLAG(ENABLE_EXTENSIONS)
 #error "Extensions must be enabled"
 #endif
 
 namespace content {
 class BrowserContext;
@@ skipping 148 matching lines @@
   // As above, but for the ready set.
   bool AddReady(const scoped_refptr<const Extension>& extension);
   bool RemoveReady(const std::string& id);
 
   // Removes all extensions from all sets.
   void ClearAll();
 
   // KeyedService implementation:
   void Shutdown() override;
 
+  LazyEventDispatchUtil* lazy_event_dispatch_util();
+
  private:
   // Extensions that are installed, enabled and not terminated.
   ExtensionSet enabled_extensions_;
 
   // Extensions that are installed and disabled.
   ExtensionSet disabled_extensions_;
 
   // Extensions that are installed and terminated.
   ExtensionSet terminated_extensions_;
 
   // Extensions that are installed and blacklisted. Generally these shouldn't be
   // considered as installed by the extension platform: we only keep them around
   // so that if extensions are blacklisted by mistake they can easily be
   // un-blacklisted.
   ExtensionSet blacklisted_extensions_;
 
   // Extensions that are installed and blocked. Will never be loaded.
   ExtensionSet blocked_extensions_;
 
   // Extensions that are ready for execution. This set is a non-exclusive
   // subset of |enabled_extensions_|.
   ExtensionSet ready_extensions_;
 
+  content::BrowserContext* const browser_context_;
+
+  std::unique_ptr<LazyEventDispatchUtil> lazy_event_dispatch_util_;

[Devlin, 2017/05/23 21:30:36]

I think this would be better placed on EventRouter.

[lazyboy, 2017/05/23 23:19:08]

Done.

+
   base::ObserverList<ExtensionRegistryObserver> observers_;
 
-  content::BrowserContext* const browser_context_;
-
   DISALLOW_COPY_AND_ASSIGN(ExtensionRegistry);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_EXTENSION_REGISTRY_H_