Revert "Build Observatory with runtime"

runtime/observatory/lib/src/elements/observatory_application.dart

-// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-library observatory_application_element;
-
-import 'observatory_element.dart';
-import 'package:observatory/app.dart';
-import 'package:polymer/polymer.dart';
-
-/// Main application tag. Responsible for instantiating an instance of
-/// [ObservatoryApplication] which is passed declaratively to all child
-/// elements.
-@CustomTag('observatory-application')
-class ObservatoryApplicationElement extends ObservatoryElement {
-  @published bool devtools = false;
-  @reflectable ObservatoryApplication app;
-
-  ObservatoryApplicationElement.created() : super.created();
-
-  @override
-  void attached() {
-    super.attached();
-    if (devtools) {
-      app = new ObservatoryApplication.devtools(this);
-    } else {
-      app = new ObservatoryApplication(this);
-    }
-  }
-}