Handle Creates and Returns annotations in KernelBehaviorBuilder

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

Index: pkg/compiler/lib/src/js_backend/backend_serialization.dart
diff --git a/pkg/compiler/lib/src/js_backend/backend_serialization.dart b/pkg/compiler/lib/src/js_backend/backend_serialization.dart
index a4e577e1fe46dea59a7101fe7ec5a63e38ed5554..1b61abf9c86d2db3d7ea9588c14f1948111329ee 100644
--- a/pkg/compiler/lib/src/js_backend/backend_serialization.dart
+++ b/pkg/compiler/lib/src/js_backend/backend_serialization.dart
@@ -160,9 +160,9 @@ class NativeBehaviorSerialization {
     if (type is DartType) {
       // TODO(johnniwinther): Remove this when annotation are no longer resolved
       // to this-types.
-      if (type is GenericType &&
-          type.isGeneric &&
-          type == type.element.thisType) {
+      if (type is InterfaceType &&
+          type.typeArguments.isNotEmpty &&
+          type.typeArguments.first is TypeVariableType) {
         return THIS_TYPE;
       }
       return NORMAL_TYPE;