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

sync/internal_api/public/util/weak_handle_unittest.cc

 // Copyright (c) 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/internal_api/public/util/weak_handle.h"
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/location.h"
 #include "base/memory/weak_ptr.h"
-#include "base/message_loop.h"
+#include "base/message_loop/message_loop.h"
 #include "base/threading/thread.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace syncer {
 
 using ::testing::_;
 using ::testing::SaveArg;
 using ::testing::StrictMock;
 
@@ skipping 295 matching lines @@
   EXPECT_FALSE(base_weak_handle.IsInitialized());
 }
 
 TEST_F(WeakHandleTest, TypeConversionConstructorUninitializedAssignment) {
   WeakHandle<Base> base_weak_handle;
   base_weak_handle = WeakHandle<Derived>();
   EXPECT_FALSE(base_weak_handle.IsInitialized());
 }
 
 }  // namespace syncer