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

chrome/browser/external_protocol/external_protocol_handler.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 "chrome/browser/external_protocol/external_protocol_handler.h"
 
 #include <set>
 
 #include "base/bind.h"
 #include "base/logging.h"
-#include "base/message_loop.h"
+#include "base/message_loop/message_loop.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/string_util.h"
 #include "base/threading/thread.h"
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/platform_util.h"
 #include "chrome/browser/prefs/scoped_user_pref_update.h"
 #include "chrome/common/pref_names.h"
 #include "content/public/browser/browser_thread.h"
@@ skipping 277 matching lines @@
 // static
 void ExternalProtocolHandler::RegisterPrefs(PrefRegistrySimple* registry) {
   registry->RegisterDictionaryPref(prefs::kExcludedSchemes);
 }
 
 // static
 void ExternalProtocolHandler::PermitLaunchUrl() {
   DCHECK_EQ(base::MessageLoop::TYPE_UI, base::MessageLoop::current()->type());
   g_accept_requests = true;
 }