Avoid to use the method pointer to Callback<>::Run on gmock tests

testing/gmock_mutant.h

 // Copyright (c) 2013 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 TESTING_GMOCK_MUTANT_H_
 #define TESTING_GMOCK_MUTANT_H_
 
 // The intention of this file is to make possible using GMock actions in
 // all of its syntactic beauty.
 //
@@ skipping 95 matching lines @@
  private:
   base::Callback<R(Args...)> cb_;
 };
 
 template <typename Signature>
 CallbackToFunctorHelper<Signature>
 CallbackToFunctor(const base::Callback<Signature>& cb) {
   return CallbackToFunctorHelper<Signature>(cb);
 }
 
+template <typename Functor>
+CallbackToFunctorHelper<typename Functor::RunType> CreateFunctor(
+    Functor functor) {
+  return CallbackToFunctor(functor);
+}
+
 template <typename Functor, typename... BoundArgs>
 CallbackToFunctorHelper<base::MakeUnboundRunType<Functor, BoundArgs...>>
 CreateFunctor(Functor functor, const BoundArgs&... args) {
   return CallbackToFunctor(base::Bind(functor, args...));
 }
 
 }  // namespace testing
 
 #endif  // TESTING_GMOCK_MUTANT_H_