Timeline service protocol support with Observatory UI

runtime/observatory/observatory_sources.gypi

 # Copyright (c) 2015, 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.
 
 # This file contains all dart, css, and html sources for Observatory.
 {
   'sources': [
     'lib/app.dart',
     'lib/base64.dart',
     'lib/cli.dart',
@@ skipping 116 matching lines @@
     'lib/src/elements/script_ref.dart',
     'lib/src/elements/script_ref.html',
     'lib/src/elements/script_view.dart',
     'lib/src/elements/script_view.html',
     'lib/src/elements/service_ref.dart',
     'lib/src/elements/service_ref.html',
     'lib/src/elements/service_view.dart',
     'lib/src/elements/service_view.html',
     'lib/src/elements/sliding_checkbox.dart',
     'lib/src/elements/sliding_checkbox.html',
+    'lib/src/elements/timeline_page.dart',
+    'lib/src/elements/timeline_page.html',
     'lib/src/elements/view_footer.dart',
     'lib/src/elements/view_footer.html',
     'lib/src/elements/vm_connect.dart',
     'lib/src/elements/vm_connect.html',
     'lib/src/elements/vm_ref.dart',
     'lib/src/elements/vm_ref.html',
     'lib/src/elements/vm_view.dart',
     'lib/src/elements/vm_view.html',
     'lib/src/elements/css/shared.css',
     'lib/src/elements/img/chromium_icon.png',
     'lib/src/elements/img/dart_icon.png',
     'lib/src/elements/img/isolate_icon.png',
     'lib/src/service/object.dart',
     'lib/tracer.dart',
     'lib/utils.dart',
     'web/index.html',
     'web/main.dart',
     'web/favicon.ico',
+    'web/third_party/trace_viewer_full.html',
+    'web/timeline.js',
+    'web/timeline.html',
   ],
 }