Use ScopedTaskEnvironment instead of MessageLoop in content unit tests.

content/browser/fileapi/sandbox_file_system_backend_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 "storage/browser/fileapi/sandbox_file_system_backend.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <set>
 
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/macros.h"
 #include "base/run_loop.h"
+#include "base/test/scoped_task_environment.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "content/public/test/test_file_system_options.h"
 #include "storage/browser/fileapi/file_system_backend.h"
 #include "storage/browser/fileapi/file_system_url.h"
 #include "storage/browser/fileapi/sandbox_file_system_backend_delegate.h"
 #include "storage/common/fileapi/file_system_util.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "url/gurl.h"
 
 using storage::FileSystemURL;
@@ skipping 94 matching lines @@
       *root_path = returned_root_path;
     return !returned_root_path.empty();
   }
 
   base::FilePath file_system_path() const {
     return data_dir_.GetPath().Append(
         SandboxFileSystemBackendDelegate::kFileSystemDirectory);
   }
 
   base::ScopedTempDir data_dir_;
-  base::MessageLoop message_loop_;
+  base::test::ScopedTaskEnvironment scoped_task_environment_;
   std::unique_ptr<storage::SandboxFileSystemBackendDelegate> delegate_;
   std::unique_ptr<storage::SandboxFileSystemBackend> backend_;
 };
 
 TEST_F(SandboxFileSystemBackendTest, Empty) {
   SetUpNewBackend(CreateAllowFileAccessOptions());
   std::unique_ptr<SandboxFileSystemBackendDelegate::OriginEnumerator>
       enumerator(CreateOriginEnumerator());
   ASSERT_TRUE(enumerator->Next().is_empty());
 }
@@ skipping 160 matching lines @@
                             storage::OPEN_FILE_SYSTEM_CREATE_IF_NONEXISTENT,
                             &root_path));
     base::FilePath expected = file_system_path().AppendASCII(
         kRootPathFileURITestCases[i].expected_path);
     EXPECT_EQ(expected.value(), root_path.value());
     EXPECT_TRUE(base::DirectoryExists(root_path));
   }
 }
 
 }  // namespace content