Refactor sync notifier out of sync api.

chrome/browser/sync/notifier/sync_notifier.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.
+//
+// Interface to the sync notifier, which is an object that receives
+// notifications when updates are available for a set of sync types.
+// All the observers are notified when such an event happens.
+
+#ifndef CHROME_BROWSER_SYNC_NOTIFIER_SYNC_NOTIFIER_H_
+#define CHROME_BROWSER_SYNC_NOTIFIER_SYNC_NOTIFIER_H_
+
+#include <string>
+
+#include "chrome/browser/sync/syncable/model_type.h"
+
+namespace sync_notifier {
+class SyncNotifierObserver;
+
+class SyncNotifier {
+ public:
+  SyncNotifier() {}
+  virtual ~SyncNotifier() {}
+
+  virtual void AddObserver(SyncNotifierObserver* observer) = 0;
+  virtual void RemoveObserver(SyncNotifierObserver* observer) = 0;
+
+  // SetState must be called once, before any call to UpdateCredentials.
+  virtual void SetState(const std::string& state) = 0;
+
+  // The observers won't be notified of any notifications until
+  // UpdateCredentials is called at least once. It can be called more than
+  // once.
+  virtual void UpdateCredentials(
+      const std::string& email, const std::string& token) = 0;
+
+  virtual void UpdateEnabledTypes(const syncable::ModelTypeSet& types) = 0;
+
+  // This is here only to support the old p2p notification implementation,
+  // which is still used by sync integration tests.
+  // TODO(akalin): Remove this once we move the integration tests off p2p
+  // notifications.
+  virtual void SendNotification() = 0;
+};
+}  // namespace sync_notifier
+
+#endif  // CHROME_BROWSER_SYNC_NOTIFIER_SYNC_NOTIFIER_H_
+