[storage] Replace MessageLoopProxy usage with ThreadTaskRunnerHandle

storage/browser/database/database_quota_client.h

 // Copyright (c) 2011 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 STORAGE_BROWSER_DATABASE_DATABASE_QUOTA_CLIENT_H_
 #define STORAGE_BROWSER_DATABASE_DATABASE_QUOTA_CLIENT_H_
 
 #include <set>
 #include <string>
 
 #include "base/memory/ref_counted.h"
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/single_thread_task_runner.h"
 #include "storage/browser/quota/quota_client.h"
 #include "storage/browser/storage_browser_export.h"
 #include "storage/common/quota/quota_types.h"
 
 namespace storage {
 
 class DatabaseTracker;
 
 // A QuotaClient implementation to integrate WebSQLDatabases
 // with the quota  management system. This interface is used
 // on the IO thread by the quota manager.
 class STORAGE_EXPORT_PRIVATE DatabaseQuotaClient
     : public storage::QuotaClient {
  public:
   DatabaseQuotaClient(
-      base::MessageLoopProxy* tracker_thread,
+      base::SingleThreadTaskRunner* tracker_thread,
       DatabaseTracker* tracker);
   ~DatabaseQuotaClient() override;
 
   // QuotaClient method overrides
   ID id() const override;
   void OnQuotaManagerDestroyed() override;
   void GetOriginUsage(const GURL& origin_url,
                       storage::StorageType type,
                       const GetUsageCallback& callback) override;
   void GetOriginsForType(storage::StorageType type,
                          const GetOriginsCallback& callback) override;
   void GetOriginsForHost(storage::StorageType type,
                          const std::string& host,
                          const GetOriginsCallback& callback) override;
   void DeleteOriginData(const GURL& origin,
                         storage::StorageType type,
                         const DeletionCallback& callback) override;
   bool DoesSupport(storage::StorageType type) const override;
 
  private:
-  scoped_refptr<base::MessageLoopProxy> db_tracker_thread_;
+  scoped_refptr<base::SingleThreadTaskRunner> db_tracker_thread_;
   scoped_refptr<DatabaseTracker> db_tracker_;  // only used on its thread
 
   DISALLOW_COPY_AND_ASSIGN(DatabaseQuotaClient);
 };
 
 }  // namespace storage
 
 #endif  // STORAGE_BROWSER_DATABASE_DATABASE_QUOTA_CLIENT_H_