pp: add test for raw strs in non-expression positions

Author: ben0x539

src/test/pretty/raw-str-nonexpr.rs

@@ -0,0 +1,16 @@
+// Copyright 2012 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.
+
+// pp-exact
+
+#[cfg = r#"just parse this"#]
+extern mod blah = r##"blah"##;
+
+fn main() { unsafe { asm!(r###"blah"###); } }