Use a direct include of the message_loop header in chrome/browser/, part 7.

chrome/browser/metrics/variations/variations_request_scheduler_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 "chrome/browser/metrics/variations/variations_request_scheduler.h"
 
 #include "base/bind.h"
-#include "base/message_loop.h"
+#include "base/message_loop/message_loop.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace chrome_variations {
 
 namespace {
 
 void DoNothing() {
 }
 
 }  // namespace
 
 TEST(VariationsRequestSchedulerTest, ScheduleFetchShortly) {
   base::MessageLoopForUI message_loop_;
 
   const base::Closure task = base::Bind(&DoNothing);
   VariationsRequestScheduler scheduler(task);
   EXPECT_FALSE(scheduler.one_shot_timer_.IsRunning());
 
   scheduler.ScheduleFetchShortly();
   EXPECT_TRUE(scheduler.one_shot_timer_.IsRunning());
 }
 
 }  // namespace chrome_variations