[Sync] Migrate SyncInternalsMessageHandler off CallJavascriptFunctionUnsafe.

components/sync/driver/about_sync_util.h

 // 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.
 
 #ifndef COMPONENTS_SYNC_DRIVER_ABOUT_SYNC_UTIL_H_
 #define COMPONENTS_SYNC_DRIVER_ABOUT_SYNC_UTIL_H_
 
 #include <memory>
 
 #include "components/version_info/version_info.h"
 
-class SigninManagerBase;
-
 namespace base {
 class DictionaryValue;
 }
 
 namespace syncer {
 
 class SyncService;
 
 namespace sync_ui_util {
 
@@ skipping 37 matching lines @@
 extern const char kOnReceivedListOfTypes[];
 extern const char kStatus[];
 extern const char kTypes[];
 extern const char kUpdate[];
 
 // This function returns a DictionaryValue which contains all the information
 // required to populate the 'About' tab of about:sync.
 // Note that |service| may be null.
 std::unique_ptr<base::DictionaryValue> ConstructAboutInformation(
     SyncService* service,
-    SigninManagerBase* signin,
     version_info::Channel channel);
 
 }  // namespace sync_ui_util
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_DRIVER_ABOUT_SYNC_UTIL_H_