Migrate invalidator client IDs out of sync

sync/notifier/invalidation_state_tracker.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.
 //
 // An InvalidationStateTracker is an interface that handles persisting state
 // needed for invalidations. Currently, it is responsible for managing the
 // following information:
 // - Max version seen from the invalidation server to help dedupe invalidations.
 // - Bootstrap data for the invalidation client.
 // - Payloads and locally generated ack handles, to support local acking.
@@ skipping 44 matching lines @@
   virtual InvalidationStateMap GetAllInvalidationStates() const = 0;
 
   // |max_version| should be strictly greater than any existing max
   // version for |model_type|.
   virtual void SetMaxVersionAndPayload(const invalidation::ObjectId& id,
                                        int64 max_version,
                                        const std::string& payload) = 0;
   // Removes all state tracked for |ids|.
   virtual void Forget(const ObjectIdSet& ids) = 0;
 
+  // The per-client unique ID used to register the invalidation client with the
+  // server.  This is used to squelch invalidation notifications that originate
+  // from changes made by this client.
+  virtual void SetInvalidatorClientId(const std::string& data) = 0;
+  virtual std::string GetInvalidatorClientId() const = 0;
+
   // Used by invalidation::InvalidationClient for persistence. |data| is an
   // opaque blob that an invalidation client can use after a restart to
   // bootstrap itself. |data| is binary data (not valid UTF8, embedded nulls,
   // etc).
   virtual void SetBootstrapData(const std::string& data) = 0;
   virtual std::string GetBootstrapData() const = 0;
 
   // Used for generating our own local ack handles. Generates a new ack handle
   // for each object id in |ids|. The result is returned via |callback| posted
   // to |task_runner|.
   virtual void GenerateAckHandles(
       const ObjectIdSet& ids,
       const scoped_refptr<base::TaskRunner>& task_runner,
       base::Callback<void(const AckHandleMap&)> callback) = 0;
 
   // Records an acknowledgement for |id|. Note that no attempt at ordering is
   // made. Acknowledge() only records the last ack_handle it received, even if
   // the last ack_handle it received was generated before the value currently
   // recorded.
   virtual void Acknowledge(const invalidation::ObjectId& id,
                            const AckHandle& ack_handle) = 0;
 
  protected:
   virtual ~InvalidationStateTracker() {}
 };
 
 }  // namespace syncer
 
 #endif  // SYNC_NOTIFIER_INVALIDATION_STATE_TRACKER_H_