Add test for #4228.

Author: luqmana

src/test/run-pass/issue-4228.rs

@@ -0,0 +1,23 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+struct Foo;
+
+impl Foo {
+    fn first() {}
+}
+impl Foo {
+    fn second() {}
+}
+
+pub fn main() {
+    Foo::first();
+    Foo::second();
+}