Remove assumption from recovery code

Author: estebank

src/libsyntax/parse/parser.rs

@@ -8366,11 +8366,11 @@ impl<'a> Parser<'a> {
                 } else {
                     ("fn` or `struct", "function or struct", true)
                 };
-                self.consume_block(token::Brace);
 
                 let msg = format!("missing `{}` for {} definition", kw, kw_name);
                 let mut err = self.diagnostic().struct_span_err(sp, &msg);
                 if !ambiguous {
+                    self.consume_block(token::Brace);
                     let suggestion = format!("add `{}` here to parse `{}` as a public {}",
                                              kw,
                                              ident,

src/test/ui/pub/pub-ident-fn-3.rs

@@ -0,0 +1,8 @@
+// #60115
+
+mod foo {
+    pub bar();
+    //~^ ERROR missing `fn` or `struct` for function or struct definition
+}
+
+fn main() {}

src/test/ui/pub/pub-ident-fn-3.stderr

@@ -0,0 +1,8 @@
+error: missing `fn` or `struct` for function or struct definition
+  --> $DIR/pub-ident-fn-3.rs:4:8
+   |
+LL |     pub bar();
+   |     ---^--- help: if you meant to call a macro, try: `bar!`
+
+error: aborting due to previous error
+