Use a direct include of the message_loop header in ppapi/, printing/, rlz/, sync/.

sync/sessions/sync_session_unittest.cc

 // Copyright 2012 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 "sync/sessions/sync_session.h"
 
 #include "base/compiler_specific.h"
 #include "base/location.h"
 #include "base/memory/ref_counted.h"
-#include "base/message_loop.h"
+#include "base/message_loop/message_loop.h"
 #include "sync/engine/syncer_types.h"
 #include "sync/internal_api/public/base/model_type.h"
 #include "sync/internal_api/public/base/model_type_invalidation_map_test_util.h"
 #include "sync/sessions/status_controller.h"
 #include "sync/syncable/syncable_id.h"
 #include "sync/syncable/syncable_write_transaction.h"
 #include "sync/test/engine/fake_model_worker.h"
 #include "sync/test/engine/test_directory_setter_upper.h"
 #include "sync/test/fake_extensions_activity_monitor.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 174 matching lines @@
 
   ASSERT_EQ(3U, invalidation_map.size());
   EXPECT_EQ(invalidation_map[BOOKMARKS].payload, payload);
   EXPECT_EQ(invalidation_map[PASSWORDS].payload, payload);
   EXPECT_EQ(invalidation_map[AUTOFILL].payload, payload);
 }
 
 }  // namespace
 }  // namespace sessions
 }  // namespace syncer