Fix ident_key macro

Summary:
It was not functional, every key was called `name`.

X-link: facebookexperimental/allocative#15

Reviewed By: IanChilds

Differential Revision: D67859121

Pulled By: KapJI

fbshipit-source-id: 3742329562daccbd9af12e19a9391783f3a797ee

allocative/allocative/src/lib.rs

@@ -103,7 +103,12 @@ pub mod __macro_refs {
 #[macro_export]
 macro_rules! ident_key {
     ($name:ident) => {{
-        const KEY: $crate::Key = $crate::Key::new(stringify!(name));
+        const KEY: $crate::Key = $crate::Key::new(stringify!($name));
         KEY
     }};
 }
+
+#[test]
+fn ident_key() {
+    assert_eq!(ident_key!(foo), Key::new("foo"));
+}