swift234

Implement selector argument syntax for method calls.

Introduce a second syntax for method calls that better describes
messages with multiple selector pieces, e.g.,

    undoManager.(registerUndoWithTarget:this
                               selector:"setItemName:"
                                 object:nameSetter)

Note that we're also allowing ':' as a separator for normal keyword
arguments. The intent is to drop the use of '=' for normal keyword
arguments, but that will be a separate change affecting a number of
test cases.



Swift SVN r4313