try blocks don't parse after return

[scottmcm]

Simple demo that won't compile but should be a type error:

#![feature(try_blocks)]
fn demo() {
    return try { 4 };
}

But it gives a parse error instead:

error: expected one of `.`, `;`, `?`, `}`, or an operator, found reserved keyword `try`
 --> src/lib.rs:3:12
  |
3 |     return try { 4 };
  |            ^^^ expected one of `.`, `;`, `?`, `}`, or an operator

error: aborting due to previous error

(It works if you put parens, like return (try { 4 });)