various: translation resources from cg backend

Extend `CodegenBackend` trait with a function returning the translation
resources from the codegen backend, which can be added to the complete
list of resources provided to the emitter.

Signed-off-by: David Wood <david.wood@huawei.com>

compiler/rustc_interface/src/tests.rs

@@ -50,7 +50,7 @@ fn mk_session(matches: getopts::Matches) -> (Session, CfgSpecs) {
         output_file: None,
         temps_dir,
     };
-    let sess = build_session(sessopts, io, None, registry, &[], Default::default(), None, None);
+    let sess = build_session(sessopts, io, None, registry, vec![], Default::default(), None, None);
     (sess, cfg)
 }
 

compiler/rustc_interface/src/util.rs

@@ -90,6 +90,9 @@ pub fn create_session(
         }
     };
 
+    let mut locale_resources = Vec::from(locale_resources);
+    locale_resources.push(codegen_backend.locale_resource());
+
     let mut sess = session::build_session(
         sopts,
         io,