Adjust orphan rules to consider all input types, not just self type.

Fixes #18222.

src/test/auxiliary/coherence-orphan-lib.rs

@@ -0,0 +1,14 @@
+// Copyright 2014 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.
+
+pub trait TheTrait<T> {
+    fn the_fn(&self);
+}
+

src/test/compile-fail/coherence-orphan.rs

@@ -0,0 +1,25 @@
+// Copyright 2014 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.
+
+// aux-build:coherence-orphan-lib.rs
+
+extern crate "coherence-orphan-lib" as lib;
+
+use lib::TheTrait;
+
+struct TheType;
+
+impl TheTrait<uint> for int { } //~ ERROR E0117
+
+impl TheTrait<TheType> for int { }
+
+impl TheTrait<int> for TheType { }
+
+fn main() { }