Setting toolbarVisible is ignored when initial animations are not finished on iOS

Initially setting the property to `false` doesn't have any effect. It must be set in the resize event of the page for it to work.

Workaround:

```
tabris.create("Page", {
title: "Creating a fullscreen page",
topLevel: true
}).once("resize", function() {
tabris.ui.set("toolbarVisible", true);
}).open();
```