sync: Move migration signal out of snapshot

sync/internal_api/sync_manager_impl.h

 // Copyright 2012 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 SYNC_INTERNAL_API_SYNC_MANAGER_H_
 #define SYNC_INTERNAL_API_SYNC_MANAGER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 122 matching lines @@
       base::Time explicit_passphrase_time) OVERRIDE;
 
   static int GetDefaultNudgeDelay();
   static int GetPreferencesNudgeDelay();
 
   // SyncEngineEventListener implementation.
   virtual void OnSyncCycleEvent(const SyncCycleEvent& event) OVERRIDE;
   virtual void OnActionableError(const SyncProtocolError& error) OVERRIDE;
   virtual void OnRetryTimeChanged(base::Time retry_time) OVERRIDE;
   virtual void OnThrottledTypesChanged(ModelTypeSet throttled_types) OVERRIDE;
+  virtual void OnMigrationRequested(ModelTypeSet types) OVERRIDE;
 
   // ServerConnectionEventListener implementation.
   virtual void OnServerConnectionEvent(
       const ServerConnectionEvent& event) OVERRIDE;
 
   // JsBackend implementation.
   virtual void SetJsEventHandler(
       const WeakHandle<JsEventHandler>& event_handler) OVERRIDE;
   virtual void ProcessJsMessage(
       const std::string& name, const JsArgList& args,
@@ skipping 224 matching lines @@
   scoped_ptr<SyncEncryptionHandlerImpl> sync_encryption_handler_;
 
   base::WeakPtrFactory<SyncManagerImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncManagerImpl);
 };
 
 }  // namespace syncer
 
 #endif  // SYNC_INTERNAL_API_SYNC_MANAGER_H_