Use ScopedTaskEnvironment instead of MessageLoop in content unit tests.

content/browser/fileapi/local_file_util_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 <stdint.h>
 
 #include <memory>
 #include <string>
 
 #include "base/files/file.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/macros.h"
 #include "base/run_loop.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/test/scoped_task_environment.h"
 #include "build/build_config.h"
 #include "content/public/test/async_file_test_helper.h"
 #include "content/public/test/test_file_system_context.h"
 #include "storage/browser/fileapi/async_file_util_adapter.h"
 #include "storage/browser/fileapi/file_system_context.h"
 #include "storage/browser/fileapi/file_system_file_util.h"
 #include "storage/browser/fileapi/file_system_operation_context.h"
 #include "storage/browser/fileapi/local_file_util.h"
 #include "storage/browser/fileapi/native_file_util.h"
 #include "storage/common/fileapi/file_system_types.h"
@@ skipping 86 matching lines @@
     std::unique_ptr<FileSystemOperationContext> context(NewContext());
     return file_util()->EnsureFileExists(context.get(),
                                          CreateURL(file_name), created);
   }
 
   FileSystemContext* file_system_context() {
     return file_system_context_.get();
   }
 
  private:
-  base::MessageLoop message_loop_;
+  base::test::ScopedTaskEnvironment scoped_task_environment_;
   scoped_refptr<FileSystemContext> file_system_context_;
   base::ScopedTempDir data_dir_;
 
   DISALLOW_COPY_AND_ASSIGN(LocalFileUtilTest);
 };
 
 TEST_F(LocalFileUtilTest, CreateAndClose) {
   const char *file_name = "test_file";
   base::File file = CreateFile(file_name);
   ASSERT_TRUE(file.IsValid());
@@ skipping 237 matching lines @@
                                       CreateURL(from_dir),
                                       CreateURL(to_dir)));
 
   EXPECT_FALSE(DirectoryExists(from_dir));
   EXPECT_TRUE(DirectoryExists(to_dir));
   EXPECT_TRUE(FileExists(to_file));
   EXPECT_EQ(1020, GetSize(to_file));
 }
 
 }  // namespace content