Tests for `void`.

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

Index: pkg/compiler/lib/src/js_backend/namer.dart
diff --git a/pkg/compiler/lib/src/js_backend/namer.dart b/pkg/compiler/lib/src/js_backend/namer.dart
index 7b7300a9fcadf3c2fadf01d3fc3042092aae15d4..324b0216cf2a9dc9235114d8f922e811d887da49 100644
--- a/pkg/compiler/lib/src/js_backend/namer.dart
+++ b/pkg/compiler/lib/src/js_backend/namer.dart
@@ -643,6 +643,9 @@ class Namer {
       case JsGetName.FUNCTION_CLASS_TYPE_NAME:
         ClassElement functionClass = commonElements.functionClass;
         return runtimeTypeName(functionClass);
+      case JsGetName.VOID_CLASS_TYPE_NAME:
+        ClassElement voidClass = helpers.voidClass;
+        return runtimeTypeName(voidClass);
       default:
         reporter.reportErrorMessage(node, MessageKind.GENERIC,
             {'text': 'Error: Namer has no name for "$name".'});