[Sync] Implement EstimateMemoryUsage for SharedModelTypeProcessor and ModelTypeWorker

components/sync/engine_impl/worker_entity_tracker.h

 // Copyright 2014 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 COMPONENTS_SYNC_ENGINE_IMPL_WORKER_ENTITY_TRACKER_H_
 #define COMPONENTS_SYNC_ENGINE_IMPL_WORKER_ENTITY_TRACKER_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 57 matching lines @@
   // is out of date.
   bool ReceiveEncryptedUpdate(const UpdateResponseData& data);
 
   // Functions to fetch the latest encrypted update.
   bool HasEncryptedUpdate() const;
   UpdateResponseData GetEncryptedUpdate() const;
 
   // Clears the encrypted update. Allows us to resume regular commit behavior.
   void ClearEncryptedUpdate();
 
+  // Returns the estimate of dynamically allocated memory in bytes.
+  size_t EstimateMemoryUsage() const;
+
   const std::string& id() const { return id_; }
   const std::string& client_tag_hash() const { return client_tag_hash_; }
 
  private:
   // Checks if the current state indicates a conflict.
   //
   // This can be true only while a call to this object is in progress.
   // Conflicts are always cleared before the method call ends.
   bool IsInConflict() const;
 
@@ skipping 33 matching lines @@
   // of an pending update prevents commits. As of this writing, the only
   // source of pending updates is updates that can't currently be decrypted.
   std::unique_ptr<UpdateResponseData> encrypted_update_;
 
   DISALLOW_COPY_AND_ASSIGN(WorkerEntityTracker);
 };
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_ENGINE_IMPL_WORKER_ENTITY_TRACKER_H_