Remove remaining calls to deprecated MessageLoop methods.

mojo/public/cpp/bindings/tests/request_response_unittest.cc

 // Copyright 2014 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 <utility>
 
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "mojo/public/cpp/bindings/binding.h"
@@ skipping 67 matching lines @@
 void RecordEnum(sample::Enum* storage,
                 const base::Closure& closure,
                 sample::Enum value) {
   *storage = value;
   closure.Run();
 }
 
 class RequestResponseTest : public testing::Test {
  public:
   RequestResponseTest() {}
-  ~RequestResponseTest() override { loop_.RunUntilIdle(); }
+  ~RequestResponseTest() override { base::RunLoop().RunUntilIdle(); }
 
-  void PumpMessages() { loop_.RunUntilIdle(); }
+  void PumpMessages() { base::RunLoop().RunUntilIdle(); }
 
  private:
   base::MessageLoop loop_;
 };
 
 TEST_F(RequestResponseTest, EchoString) {
   sample::ProviderPtr provider;
   ProviderImpl provider_impl(GetProxy(&provider));
 
   std::string buf;
@@ skipping 48 matching lines @@
   provider->EchoEnum(sample::Enum::VALUE,
                      base::Bind(&RecordEnum, &value, run_loop.QuitClosure()));
   run_loop.Run();
 
   EXPECT_EQ(sample::Enum::VALUE, value);
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace mojo