fix #30030, fix #27327 - fix tearoffs and various Object member bugs

pkg/dev_compiler/lib/src/compiler/js_typeref_codegen.dart

Index: pkg/dev_compiler/lib/src/compiler/js_typeref_codegen.dart
diff --git a/pkg/dev_compiler/lib/src/compiler/js_typeref_codegen.dart b/pkg/dev_compiler/lib/src/compiler/js_typeref_codegen.dart
index 28bb62697f891131c661f9ce32f210817f4a1133..d8b8902e63990c5d4dcedb3639a4e0e1f1e2ca41 100644
--- a/pkg/dev_compiler/lib/src/compiler/js_typeref_codegen.dart
+++ b/pkg/dev_compiler/lib/src/compiler/js_typeref_codegen.dart
@@ -25,8 +25,10 @@ abstract class JsTypeRefCodegen {
   /// Finds the qualified path to the type.
   JS.TypeRef _emitTopLevelTypeRef(DartType type) {
     var e = type.element;
-    return new JS.TypeRef.qualified(
-        [emitLibraryName(e.library), new JS.Identifier(getJSExportName(e))]);
+    return new JS.TypeRef.qualified([
+      emitLibraryName(e.library),
+      new JS.Identifier(getJSExportName(e) ?? e.name)
+    ]);
   }
 
   JS.TypeRef emitTypeRef(DartType type) {