Splitting MOCK_METHOD declaration and definition

I'm working with classes that mocks a lot of methods and each MOCK_METHODxx results in method beining defined in each translation unit. Cookbook mentions defining constructor and destructor for mocks in separate .cpp file so it can be reused, it seems that it makes sense to split declaration and definition of each MOCK_METHOD in order to save some compilation time.

There is closed PR implementing this: https://github.com/google/googletest/pull/1592. Would you be interested in pull request with similar functionality?