Fixed race condition in test. Fixed spurious wait requests on shutdown.

chrome/test/data/webrtc/message_handling.js

 /**
  * Copyright (c) 2012 The Chromium Authors. 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 requires these functions to be defined globally by someone else:
 // function handleMessage(peerConnection, message)
 // function createPeerConnection(stun_server)
 // function setupCall(peerConnection)
@@ skipping 107 matching lines @@
  * Disconnects from the peerconnection server. Returns ok-disconnected on
  * success.
  */
 function disconnect() {
   if (gOurPeerId == null)
     failTest('Disconnecting, but we are not connected.');
 
   request = new XMLHttpRequest();
   request.open("GET", gServerUrl + "/sign_out?peer_id=" + gOurPeerId, false);
   request.send();
-  request = null;
   gOurPeerId = null;
   returnToPyAuto('ok-disconnected');
 }
 
 // Internals.
 
+function isDisconnected() {
+  return gOurPeerId == null;
+}
+
 function connectCallback(request) {
   debug("Connect callback: " + request.status + ", " + request.readyState);
   if (request.readyState == 4 && request.status == 200) {
     gOurPeerId = parseOurPeerId(request.responseText);
     gRemotePeerId = parseRemotePeerIdIfConnected(request.responseText);
     startHangingGet(gServerUrl, gOurPeerId);
     returnToPyAuto('ok-connected');
   }
 }
 
@@ skipping 27 matching lines @@
         failTest('Unexpected second peer');
 
       // Found a remote peer.
       remotePeerId = id;
     }
   }
   return remotePeerId;
 }
 
 function startHangingGet(server, ourId) {
+  if (isDisconnected())
+    return;
   hangingGetRequest = new XMLHttpRequest();
   hangingGetRequest.onreadystatechange = function() {
     hangingGetCallback(hangingGetRequest, server, ourId);
   }
   hangingGetRequest.ontimeout = function() {
     hangingGetTimeoutCallback(hangingGetRequest, server, ourId);
   }
   callUrl = server + "/wait?peer_id=" + ourId;
   debug('Sending ' + callUrl);
   hangingGetRequest.open("GET", callUrl, true);
@@ skipping 87 matching lines @@
 
 function readResponseHeader(request, key) {
   var value = request.getResponseHeader(key)
   if (value == null || value.length == 0) {
     addTestFailure('Received empty value ' + value +
                    ' for response header key ' + key + '.');
     return -1;
   }
   return parseInt(value);
 }