Automatically fetch timeline when timeline page is loaded

runtime/observatory/web/timeline.js

 // 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.
 
+// Used to delay the initial timeline load until the timeline has finished
+// loading.
+timeline_loaded = false;
+timeline_vm_address = undefined;
+timeline_isolates = undefined;
+
+function registerForMessages() {
+  window.addEventListener("message", onMessage, false);
+}
+
+registerForMessages();
+
 function onModelLoaded() {
   viewer.globalMode = true;
   viewer.model = model;
 }
 
 function clearTimeline() {
   viewer.model = undefined;
 }
 
 function onImportFail() {
   var overlay = new tr.ui.b.Overlay();
   overlay.textContent = tr.b.normalizeException(err).message;
   overlay.title = 'Import error';
   overlay.visible = true;
   console.log('import failed');
 }
 
 function updateTimeline(events) {
   model = new tr.Model();
   var importer = new tr.importer.Import(model);
   var p = importer.importTracesWithProgressDialog([events]);
   p.then(onModelLoaded, onImportFail);
 }
 
-function registerForMessages() {
-  window.addEventListener("message", onMessage, false);
-}
+
 
 function fetchUri(uri, onLoad, onError) {
   var xhr = new XMLHttpRequest();
   xhr.open('GET', uri, true);
   xhr.responseType = 'text';
   xhr.addEventListener("load", onLoad);
   xhr.addEventListener("error", onError);
   xhr.send();
   console.log('GET ' + uri);
 }
@@ skipping 147 matching lines @@
   });
   inputElement.click();
 }
 
 function onMessage(event) {
   var request = JSON.parse(event.data);
   var method = request['method'];
   var params = request['params'];
   switch (method) {
     case 'refresh':
-      fetchTimeline(params['vmAddress'], params['isolateIds']);
+      if (!timeline_loaded) {
+        timeline_vm_address = params['vmAddress'];
+        timeline_isolates = params['isolateIds'];
+        console.log('Delaying timeline refresh until loaded.');
+      } else {
+        fetchTimeline(params['vmAddress'], params['isolateIds']);
+      }
     break;
     case 'clear':
       clearTimeline();
     break;
     case 'save':
       saveTimeline();
     break;
     case 'load':
       loadTimeline();
     break;
     default:
       console.log('Unknown method:' + method + '.');
   }
 }
 
 document.addEventListener('DOMContentLoaded', function() {
   var container = document.createElement('track-view-container');
   container.id = 'track_view_container';
   viewer = document.createElement('tr-ui-timeline-view');
   viewer.track_view_container = container;
   viewer.appendChild(container);
   viewer.id = 'trace-viewer';
   viewer.globalMode = true;
   document.body.appendChild(viewer);
-  registerForMessages();
+  timeline_loaded = true;
+  if (timeline_vm_address != undefined) {
+    console.log('Triggering delayed timeline refresh.');
+    fetchTimeline(timeline_vm_address, timeline_isolates);
+    timeline_vm_address = undefined;
+    timeline_isolates = undefined;
+  }
 });
 
 console.log('loaded');