Refactor Observatory

runtime/bin/vmservice/client/lib/src/observatory_elements/stack_trace.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 stack_trace_element;
-
-import 'dart:html';
-import 'package:logging/logging.dart';
-import 'package:polymer/polymer.dart';
-import 'observatory_element.dart';
-
-@CustomTag('stack-trace')
-class StackTraceElement extends ObservatoryElement {
-  @published Map trace = toObservable({});
-
-  StackTraceElement.created() : super.created();
-
-  void refresh(var done) {
-    var url = app.locationManager.currentIsolateRelativeLink('stacktrace');
-    app.requestManager.requestMap(url).then((map) {
-        trace = map;
-    }).catchError((e, trace) {
-        Logger.root.severe('Error while reloading stack trace: $e\n$trace');
-    }).whenComplete(done);
-  }
-}