Make NotificationService an interface in the content namespace, and switch callers to use it. Mov...

content/public/browser/notification_service.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.
+
+// This file describes a central switchboard for notifications that might
+// happen in various parts of the application, and allows users to register
+// observers for various classes of events that they're interested in.
+
+#ifndef CONTENT_PUBLIC_NOTIFICATION_SERVICE_H_
+#define CONTENT_PUBLIC_NOTIFICATION_SERVICE_H_
+#pragma once
+
+#include "content/common/content_export.h"
+#include "content/public/browser/notification_details.h"
+#include "content/public/browser/notification_source.h"
+
+namespace content {
+
+class NotificationService {
+ public:
+  // Returns the NotificationService object for the current thread, or NULL if
+  // none.
+  static CONTENT_EXPORT NotificationService* current();
+
+  virtual ~NotificationService() {}
+
+  // Synchronously posts a notification to all interested observers.
+  // Source is a reference to a NotificationSource object representing
+  // the object originating the notification (can be
+  // NotificationService::AllSources(), in which case
+  // only observers interested in all sources will be notified).
+  // Details is a reference to an object containing additional data about
+  // the notification.  If no additional data is needed, NoDetails() is used.
+  // There is no particular order in which the observers will be notified.
+  virtual void Notify(int type,
+              const NotificationSource& source,
+              const NotificationDetails& details) = 0;

[Avi (use Gerrit), 2011/10/19 21:49:18]

alignment

+
+  // Returns a NotificationSource that represents all notification sources
+  // (for the purpose of registering an observer for events from all sources).
+  static Source<void> AllSources() { return Source<void>(NULL); }
+
+  // Returns the same value as AllSources(). This function has semantic
+  // differences to the programmer: We have checked that this AllSources()
+  // usage is safe in the face of multiple profiles. Objects that were
+  // singletons now will always have multiple instances, one per browser
+  // context.
+  //
+  // Some usage is safe, where the Source is checked to see if it's a member of
+  // a container before use. But, we want the number of AllSources() calls to
+  // drop to almost nothing, because most usages are not multiprofile safe and
+  // were done because it was easier to listen to everything.
+  static Source<void> AllBrowserContextsAndSources() {
+    return Source<void>(NULL);
+  }
+
+  // Returns a NotificationDetails object that represents a lack of details
+  // associated with a notification.  (This is effectively a null pointer.)
+  static Details<void> NoDetails() { return content::Details<void>(NULL); }
+};
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_NOTIFICATION_SERVICE_H_