Fix pretty-printer test failure by carrying the bound lifetime names through

the types.  Initially I thought it would be necessary to thread this data
through not only the AST but the types themselves, but then I remembered that
the pretty printer only cares about the AST.  Regardless, I have elected to
leave the changes to the types intact since they will eventually be needed.  I
left a few FIXMEs where it didn't seem worth finishing up since the code wasn't
crucial yet.

src/libsyntax/parse/parser.rs

@@ -363,10 +363,11 @@ pub impl Parser {
 
         let purity = self.parse_purity();
         self.expect_keyword(&~"fn");
-        let (decl, _) = self.parse_ty_fn_decl();
+        let (decl, lifetimes) = self.parse_ty_fn_decl();
         return ty_bare_fn(@TyBareFn {
             abi: RustAbi,
             purity: purity,
+            lifetimes: lifetimes,
             decl: decl
         });
     }