Fix #53, handle non-standard setTimeout lateness.

Firefox < 13 passes an numeric argument, lateness, to
the callback for `setTimeout, which caused $yetify to re-init.

Verify the config argument is an object, instead of a number.

See: https://developer.mozilla.org/en/window.setTimeout

lib/hub/view/public/inject.js

@@ -44,7 +44,6 @@ function $yetify(firstRunConfiguration) {
 
         // TODO Throttle test navigation for Opera and slow mobile devices.
         socket.on("complete", function () {
-            if (!config.mountpoint) return;
             document.location.href = config.mountpoint;
         });
 
@@ -53,7 +52,11 @@ function $yetify(firstRunConfiguration) {
         });
     }
 
-    if (firstRunConfiguration) {
+    // $yetify will be called again from setTimeout.
+    // In Firefox < 13, the first argument may be a `lateness` argument.
+    // https://developer.mozilla.org/en/window.setTimeout
+    // Make sure this argument is an object before initializing.
+    if ("object" === typeof firstRunConfiguration) {
         init(firstRunConfiguration);
         if (document.compatMode !== "CSS1Compat") {
             throw new Error("Yeti requires HTML files with doctypes.");