swift234

Implement support for type-attributes on the result of a function type or decl.
Also, improve error recovery for new-syntax attributes.

This means that we now compile the testcase into:

t.swift:3:16: error: unknown attribute 'xyz'
var x : () -> @xyz Int
               ^
t.swift:6:16: error: unknown attribute 'xyz'
func foo() -> @xyz Int {
               ^

instead of:

t.swift:4:15: error: expected type for function result
func foo() -> @xyz Int {
              ^
t.swift:4:14: error: consecutive statements on a line must be separated by ';'
func foo() -> @xyz Int {
             ^
             ;
t.swift:4:16: error: unknown attribute 'xyz'
func foo() -> @xyz Int {
               ^
t.swift:7:1: error: expected declaration

^

this is part of rdar://15183765


Swift SVN r9260