Warn when first arg to call_user_func is an object with no __invoke
Slight non-optimality: the message should say call_user_func_array if
you're making this mistake with that function, but that would take a
little extra effort (looking at the active VM frame) and we're already
getting it wrong in other situations.
The error message doesn't match PHP, which says "no array or string
given". I'm going for more information rather than perfect matching.
Reviewed By: @ptarjan
Differential Revision:
D1170508