Bug 1174422 - Add system principal for UDPSocket init r=kitcambridge

dom/simplepush/PushService.jsm

@@ -1733,7 +1733,7 @@ this.PushService = {
 
     this._udpServer = Cc["@mozilla.org/network/udp-socket;1"]
                         .createInstance(Ci.nsIUDPSocket);
-    this._udpServer.init(-1, false);
+    this._udpServer.init(-1, false, Services.scriptSecurityManager.getSystemPrincipal());
     this._udpServer.asyncListen(this);
     debug("listenForUDPWakeup listening on " + this._udpServer.port);