[WIP][tracing] Add memory dump provider for sync Directory

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_IMPL_H_
 #define SYNC_INTERNAL_API_SYNC_MANAGER_IMPL_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 76 matching lines @@
                        const ModelSafeRoutingInfo& new_routing_info,
                        const base::Closure& ready_task,
                        const base::Closure& retry_task) override;
   void SetInvalidatorEnabled(bool invalidator_enabled) override;
   void OnIncomingInvalidation(
       syncer::ModelType type,
       std::unique_ptr<InvalidationInterface> invalidation) override;
   void AddObserver(SyncManager::Observer* observer) override;
   void RemoveObserver(SyncManager::Observer* observer) override;
   SyncStatus GetDetailedStatus() const override;
+  void OnMemoryDump(base::trace_event::ProcessMemoryDump* pmd) override;
   void SaveChanges() override;
   void ShutdownOnSyncThread(ShutdownReason reason) override;
   UserShare* GetUserShare() override;
   std::unique_ptr<syncer_v2::ModelTypeConnector> GetModelTypeConnectorProxy()
       override;
   const std::string cache_guid() override;
   bool ReceivedExperiment(Experiments* experiments) override;
   bool HasUnsyncedItems() override;
   SyncEncryptionHandler* GetEncryptionHandler() override;
   ScopedVector<syncer::ProtocolEvent> GetBufferedProtocolEvents() override;
@@ skipping 234 matching lines @@
   std::unique_ptr<SyncEncryptionHandlerImpl> sync_encryption_handler_;
 
   base::WeakPtrFactory<SyncManagerImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncManagerImpl);
 };
 
 }  // namespace syncer
 
 #endif  // SYNC_INTERNAL_API_SYNC_MANAGER_IMPL_H_