Revert 28422

runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/stack_trace.dart

Index: runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/stack_trace.dart
diff --git a/runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/stack_trace.dart b/runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/stack_trace.dart
deleted file mode 100644
index b5e22501d2a2116aff664d8fb967e57d5779a8a4..0000000000000000000000000000000000000000
--- a/runtime/bin/vmservice/client/packages/observatory/src/observatory_elements/stack_trace.dart
+++ /dev/null
@@ -1,13 +0,0 @@
-// 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 'observatory_element.dart';
-import 'package:polymer/polymer.dart';
-
-@CustomTag('stack-trace')
-class StackTraceElement extends ObservatoryElement {
-  @published Map get trace => __$trace; Map __$trace = toObservable({}); set trace(Map value) { __$trace = notifyPropertyChange(#trace, __$trace, value); }
-}