Remove calls to deprecated MessageLoop methods in extensions.

extensions/browser/file_reader_unittest.cc

 // Copyright (c) 2011 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/bind_helpers.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/path_service.h"
+#include "base/run_loop.h"
 #include "components/crx_file/id_util.h"
 #include "content/public/test/test_browser_thread.h"
 #include "extensions/browser/file_reader.h"
 #include "extensions/common/extension_paths.h"
 #include "extensions/common/extension_resource.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using content::BrowserThread;
 
 namespace extensions {
@@ skipping 41 matching lines @@
 
   std::string file_contents;
   ASSERT_TRUE(base::ReadFileToString(path, &file_contents));
 
   Receiver receiver;
 
   scoped_refptr<FileReader> file_reader(
       new FileReader(resource, receiver.NewCallback()));
   file_reader->Start();
 
-  base::MessageLoop::current()->Run();
+  base::RunLoop().Run();
 
   EXPECT_TRUE(receiver.succeeded());
   EXPECT_EQ(file_contents, receiver.data());
 }
 
 TEST_F(FileReaderTest, SmallFile) {
   RunBasicTest("smallfile");
 }
 
 TEST_F(FileReaderTest, BiggerFile) {
   RunBasicTest("bigfile");
 }
 
 TEST_F(FileReaderTest, NonExistantFile) {
   base::FilePath path;
   PathService::Get(DIR_TEST_DATA, &path);
   std::string extension_id = crx_file::id_util::GenerateId("test");
   ExtensionResource resource(extension_id, path, base::FilePath(
       FILE_PATH_LITERAL("file_that_does_not_exist")));
   path = path.AppendASCII("file_that_does_not_exist");
 
   Receiver receiver;
 
   scoped_refptr<FileReader> file_reader(
       new FileReader(resource, receiver.NewCallback()));
   file_reader->Start();
 
-  base::MessageLoop::current()->Run();
+  base::RunLoop().Run();
 
   EXPECT_FALSE(receiver.succeeded());
 }
 
 }  // namespace extensions