dart2js: fix dart2js crash when getRuntimeTypeArgument was not registered.

pkg/compiler/lib/src/js_backend/backend.dart

Index: pkg/compiler/lib/src/js_backend/backend.dart
diff --git a/pkg/compiler/lib/src/js_backend/backend.dart b/pkg/compiler/lib/src/js_backend/backend.dart
index e39689912d640397e5d405738780373d805b89af..1a3807477c27d224e17d1449a5d7e295e99a6082 100644
--- a/pkg/compiler/lib/src/js_backend/backend.dart
+++ b/pkg/compiler/lib/src/js_backend/backend.dart
@@ -2574,7 +2574,7 @@ class JavaScriptResolutionCallbacks extends ResolutionCallbacks {
     if (type.isMalformed) {
       registerBackendStaticInvocation(backend.getThrowTypeError(), registry);
     }
-    if (!type.treatAsRaw || type.containsTypeVariables) {
+    if (!type.treatAsRaw || type.containsTypeVariables || type.isFunctionType) {
       // TODO(johnniwinther): Investigate why this is needed.
       registerBackendStaticInvocation(
           backend.getSetRuntimeTypeInfo(), registry);