dart2js: don't reify type variables for reflectable typedefs.

pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart

Index: pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart
diff --git a/pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart b/pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart
index 31fdea5e63f962ac523e5f3d3a2469f4df1e7352..1ce00b514aadeffc9776c7ff539574a13841b29c 100644
--- a/pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart
+++ b/pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart
@@ -1043,7 +1043,10 @@ class OldEmitter implements Emitter {
       LibraryElement library = typedef.library;
       // TODO(karlklose): add a TypedefBuilder and move this code there.
       DartType type = typedef.alias;
-      int typeIndex = task.metadataCollector.reifyType(type);
+      // TODO(zarah): reify type variables once reflection on type arguments of
+      // typedefs is supported.
+      int typeIndex =
+          task.metadataCollector.reifyType(type, ignoreTypeVariables: true);
       ClassBuilder builder = new ClassBuilder(typedef, namer);
       builder.addProperty(embeddedNames.TYPEDEF_TYPE_PROPERTY_NAME,
                           js.number(typeIndex));