copied over cmp_owned fix from master

tests/compile-fail/cmp_owned.rs

@@ -1,4 +1,4 @@
-#![feature(plugin, collections)]
+#![feature(plugin)]
 #![plugin(clippy)]
 
 #[deny(cmp_owned)]
@@ -13,11 +13,5 @@ fn main() {
 
     x != "foo".to_owned(); //~ERROR this creates an owned instance
 
-    #[allow(deprecated)] // for from_str
-    fn old_timey(x : &str) {
-        x != String::from_str("foo"); //~ERROR this creates an owned instance
-    }
-    old_timey(x);
-
     x != String::from("foo"); //~ERROR this creates an owned instance
 }