Enable browser tests for ChromeOS.

chrome/browser/extensions/api/sync_file_system/sync_file_system_apitest.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 "base/bind.h"
 #include "base/file_util.h"
 #include "base/path_service.h"
 #include "base/run_loop.h"
 #include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/extension_apitest.h"
@@ skipping 83 matching lines @@
   base::MessageLoopProxy::current()->PostTask(
       FROM_HERE, base::Bind(arg0,
                             sync_file_system::SYNC_STATUS_OK,
                             mock_url));
   mock_remote_service->NotifyFileStatusChanged(
       mock_url, sync_direction, sync_file_status, sync_action_taken);
 }
 
 }  // namespace
 
-// TODO(calvinlo): Add Chrome OS support for syncable file system
-// (http://crbug.com/160693)
-#if !defined(OS_CHROMEOS)
-
 IN_PROC_BROWSER_TEST_F(SyncFileSystemApiTest, DeleteFileSystem) {
   ASSERT_TRUE(RunPlatformAppTest("sync_file_system/delete_file_system"))
       << message_;
 }
 
 IN_PROC_BROWSER_TEST_F(SyncFileSystemApiTest, GetFileStatus) {
   EXPECT_CALL(*mock_remote_service(), IsConflicting(_)).WillOnce(Return(true));
   ASSERT_TRUE(RunPlatformAppTest("sync_file_system/get_file_status"))
       << message_;
 }
@@ skipping 53 matching lines @@
 IN_PROC_BROWSER_TEST_F(SyncFileSystemApiTest, WriteFileThenGetUsage) {
   ASSERT_TRUE(RunPlatformAppTest("sync_file_system/write_file_then_get_usage"))
       << message_;
 }
 
 IN_PROC_BROWSER_TEST_F(SyncFileSystemApiTest, ConflictResolutionPolicy) {
   ASSERT_TRUE(RunPlatformAppTest("sync_file_system/conflict_resolution_policy"))
       << message_;
 }
 
-#endif  // !defined(OS_CHROMEOS)
-
 }  // namespace chrome