swift234

Use ParserResult and ParserStatus in tuple and function argument parsing

This finally fixes a few code completion test cases.

This also regresses the error message in one parsing testcase because
previously we would just happily skip those tokens, but now error handling path
is a little bit different and these tokens hit different error handling code.
This can be fixed by parsing a tuple for the selector argument and complaining
if the tuple had more than one element.


Swift SVN r7389