Update error messages in compile-fail tests

src/test/compile-fail/object-does-not-impl-trait.rs

@@ -14,6 +14,6 @@
 
 trait Foo {}
 fn take_foo<F:Foo>(f: F) {}
-fn take_object(f: Box<Foo>) { take_foo(f); } //~ ERROR failed to find an implementation of trait
-//~^ ERROR failed to find an implementation
+fn take_object(f: Box<Foo>) { take_foo(f); }
+//~^ ERROR the trait `Foo` is not implemented
 fn main() {}