Replace 'mutable?' with 'const'

src/comp/syntax/parse/parser.rs

@@ -746,8 +746,7 @@ fn parse_path_and_ty_param_substs(p: parser) -> ast::path {
 
 fn parse_mutability(p: parser) -> ast::mutability {
     if eat_word(p, "mutable") {
-        if p.peek() == token::QUES { p.bump(); ast::maybe_mut }
-        else { ast::mut }
+        ast::mut
     } else if eat_word(p, "const") {
         ast::maybe_mut
     } else {

src/comp/syntax/print/pprust.rs

@@ -1307,7 +1307,7 @@ fn print_op_maybe_parens(s: ps, expr: @ast::expr, outer_prec: int) {
 fn print_mutability(s: ps, mut: ast::mutability) {
     alt mut {
       ast::mut. { word_nbsp(s, "mutable"); }
-      ast::maybe_mut. { word_nbsp(s, "mutable?"); }
+      ast::maybe_mut. { word_nbsp(s, "const"); }
       ast::imm. {/* nothing */ }
     }
 }