Migrate TabControlFeature from 0.5 to 0.6

blimp/client/core/blimp_client_context_impl_unittest.cc

 // Copyright 2016 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 "blimp/client/core/blimp_client_context_impl.h"
 
+#include "base/message_loop/message_loop.h"
 #include "blimp/client/public/blimp_client_context_delegate.h"
 #include "blimp/client/public/contents/blimp_contents.h"
 #include "blimp/client/test/test_blimp_client_context_delegate.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace blimp {
 namespace client {
 namespace {
 
 TEST(BlimpClientContextImpl, CreatedBlimpContentsGetsHelpersAttached) {
+  base::MessageLoop loop;
   BlimpClientContextImpl blimp_client_context;
   TestBlimpClientContextDelegate delegate;
   blimp_client_context.SetDelegate(&delegate);
 
   std::unique_ptr<BlimpContents> blimp_contents =
       blimp_client_context.CreateBlimpContents();
   DCHECK(blimp_contents);
   DCHECK_EQ(blimp_contents.get(),
             delegate.GetBlimpContentsWithLastAttachedHelpers());
 }
 
 }  // namespace
 }  // namespace client
 }  // namespace blimp