Remove calls to deprecated MessageLoop methods in chrome.

chrome/browser/sync_file_system/drive_backend/metadata_database_unittest.cc

 // Copyright 2013 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 "chrome/browser/sync_file_system/drive_backend/metadata_database.h"
 
 #include <stdint.h>
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/message_loop/message_loop.h"
+#include "base/run_loop.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "chrome/browser/sync_file_system/drive_backend/drive_backend_constants.h"
 #include "chrome/browser/sync_file_system/drive_backend/drive_backend_test_util.h"
 #include "chrome/browser/sync_file_system/drive_backend/drive_backend_util.h"
 #include "chrome/browser/sync_file_system/drive_backend/leveldb_wrapper.h"
 #include "chrome/browser/sync_file_system/drive_backend/metadata_database.pb.h"
 #include "chrome/browser/sync_file_system/drive_backend/metadata_database_index.h"
 #include "chrome/browser/sync_file_system/drive_backend/metadata_database_index_interface.h"
 #include "chrome/browser/sync_file_system/drive_backend/metadata_database_index_on_disk.h"
@@ skipping 184 matching lines @@
   SyncStatusCode InitializeMetadataDatabase() {
     SyncStatusCode status = SYNC_STATUS_UNKNOWN;
     metadata_database_ = MetadataDatabase::CreateInternal(
         database_dir_.path(), in_memory_env_.get(),
         GetParam(), &status);
     return status;
   }
 
   void DropDatabase() {
     metadata_database_.reset();
-    message_loop_.RunUntilIdle();
+    base::RunLoop().RunUntilIdle();
   }
 
   void SetUpDatabaseByTrackedFiles(const TrackedFile** tracked_files,
                                    int size) {
     std::unique_ptr<LevelDBWrapper> db = InitializeLevelDB();
     ASSERT_TRUE(db);
 
     for (int i = 0; i < size; ++i) {
       const TrackedFile* file = tracked_files[i];
       if (file->should_be_absent)
@@ skipping 924 matching lines @@
   EXPECT_TRUE(file->HasKey("details"));
 
   ASSERT_TRUE(files->GetDictionary(1, &file));
   EXPECT_TRUE(file->GetString("title", &str) && str == "file_0");
   EXPECT_TRUE(file->GetString("type", &str) && str == "file");
   EXPECT_TRUE(file->HasKey("details"));
 }
 
 }  // namespace drive_backend
 }  // namespace sync_file_system