Revert "Update all Angular libs (run update_all.sh)."

third_party/pkg/angular/demo/helloworld/web/helloworld.dart

+import 'package:angular/angular.dart';
+
+// This annotation allows Dart to shake away any classes
+// not used from Dart code nor listed in another @MirrorsUsed.
+//
+// If you create classes that are referenced from the Angular
+// expressions, you must include a library target in @MirrorsUsed.
+@MirrorsUsed(override: '*')
+import 'dart:mirrors';
+
+@NgController(
+    selector: '[hello-world-controller]',
+    publishAs: 'ctrl')
+class HelloWorldController {
+  String name = "world";
+}
+
+main() {
+  ngBootstrap(module: new Module()..type(HelloWorldController));
+}