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

sync/internal_api/test/fake_sync_manager.cc

 // Copyright (c) 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.
 
 #include "sync/internal_api/public/test/fake_sync_manager.h"
 
 #include <cstddef>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 171 matching lines @@
 
 void FakeSyncManager::RemoveObserver(Observer* observer) {
   observers_.RemoveObserver(observer);
 }
 
 SyncStatus FakeSyncManager::GetDetailedStatus() const {
   NOTIMPLEMENTED();
   return SyncStatus();
 }
 
+void FakeSyncManager::OnMemoryDump(base::trace_event::ProcessMemoryDump* pmd) {
+  NOTIMPLEMENTED();
+}
+
 void FakeSyncManager::SaveChanges() {
   // Do nothing.
 }
 
 void FakeSyncManager::ShutdownOnSyncThread(ShutdownReason reason) {
   DCHECK(sync_task_runner_->RunsTasksOnCurrentThread());
   test_user_share_.TearDown();
 }
 
 UserShare* FakeSyncManager::GetUserShare() {
@@ skipping 64 matching lines @@
 }
 
 void FakeSyncManager::ClearServerData(const ClearServerDataCallback& callback) {
   callback.Run();
 }
 
 void FakeSyncManager::OnCookieJarChanged(bool account_mismatch,
                                          bool empty_jar) {}
 
 }  // namespace syncer