socket: fixed disconnect xhr url and made it actually sync

Author: rauchg

lib/socket.js

@@ -52,8 +52,7 @@
     if (this.options['sync disconnect on unload'] &&
         (!this.isXDomain() || io.util.ua.hasCORS)) {
       var self = this;
-
-      io.util.on(global, 'unload', function () {
+      io.util.on(global, 'beforeunload', function () {
         self.disconnectSync();
       }, false);
     }
@@ -362,11 +361,12 @@
       , this.options.host + ':' + this.options.port
       , this.options.resource
       , io.protocol
+      , ''
       , this.sessionid
-    ].join('/') + '?disconnect';
+    ].join('/') + '/?disconnect=1';
 
-    xhr.open('GET', uri, true);
-    xhr.send(null); 
+    xhr.open('GET', uri, false);
+    xhr.send(null);
 
     // handle disconnection immediately
     this.onDisconnect('booted');