Remove root resource id aliasing from DriveResourceMetadata.

chrome/browser/chromeos/drive/file_system/create_directory_operation_unittest.cc

 // Copyright (c) 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/chromeos/drive/file_system/create_directory_operation.h"
 
 #include "base/message_loop.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "chrome/browser/chromeos/drive/change_list_loader.h"
 #include "chrome/browser/chromeos/drive/drive_cache.h"
@@ skipping 36 matching lines @@
     fake_drive_service_->LoadAppListForDriveApi("chromeos/drive/applist.json");
 
     fake_free_disk_space_getter_.reset(new FakeFreeDiskSpaceGetter);
     cache_.reset(new DriveCache(DriveCache::GetCacheRootPath(profile_.get()),
                                 blocking_task_runner_,
                                 fake_free_disk_space_getter_.get()));
     cache_->RequestInitializeForTesting();
     google_apis::test_util::RunBlockingPoolTask();
 
     metadata_.reset(new DriveResourceMetadata(
-        fake_drive_service_->GetRootResourceId(),
         cache_->GetCacheDirectoryPath(DriveCache::CACHE_TYPE_META),
         blocking_task_runner_));
 
     DriveFileError error = DRIVE_FILE_ERROR_FAILED;
     metadata_->Initialize(
         google_apis::test_util::CreateCopyResultCallback(&error));
     google_apis::test_util::RunBlockingPoolTask();
     ASSERT_EQ(DRIVE_FILE_OK, error);
 
     scheduler_.reset(
@@ skipping 119 matching lines @@
   operation()->FindFirstMissingParentDirectory(
       base::FilePath(FILE_PATH_LITERAL("drive/root/Directory 1")),
       google_apis::test_util::CreateCopyResultCallback(&result));
   google_apis::test_util::RunBlockingPoolTask();
   EXPECT_EQ(CreateDirectoryOperation::FIND_FIRST_DIRECTORY_ALREADY_PRESENT,
             result.error);
 }
 
 }  // namespace file_system
 }  // namespace drive