Support mocking methods with move-only return types.


git-svn-id: http://googlemock.googlecode.com/svn/trunk@467 8415998a-534a-0410-bf83-d39667b30386
Suppress "Conditional expression is constant" warning on Visual Studio.


git-svn-id: http://googlemock.googlecode.com/svn/trunk@468 8415998a-534a-0410-bf83-d39667b30386