Revert "Build Observatory with runtime"

runtime/observatory/lib/src/elements/eval_link.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 eval_link_element;
-
-import 'package:observatory/service.dart';
-import 'package:polymer/polymer.dart';
-
-@CustomTag('eval-link')
-class EvalLinkElement extends PolymerElement {
-  EvalLinkElement.created() : super.created();
-
-  @observable bool busy = false;
-  @published String label = "[evaluate]";
-  @published var callback = null;
-  @published var expr = '';
-  @published ServiceObject result = null;
-
-  void evalNow(var a, var b, var c) {
-    if (busy) {
-      return;
-    }
-    if (callback != null) {
-      busy = true;
-      result = null;
-      callback(expr).then((ServiceObject obj) {
-          result = obj;
-        }).whenComplete(() {
-          busy = false;
-        });
-    }
-  }
-}