Disallow Await and inout counting as a final position and ignore & as a lval-as-an-expression
Summary:
Because we don't support `async` and `inout` on the same function, we shouldn't support it as a final position.
Also because &'s are slanted for removal and hack has traditionally had a firm belief they don't exist I'm going to exclude them from being counted as `lval-as-an-expression`.
Reviewed By: Matt-Schellhas
Differential Revision:
D14789082
fbshipit-source-id:
7d23d77bd84f4ae976a59528588f0b7a05badb0c