Correctly update "list all tabs" menu if there is pinned tabs

Also may be fixed using following way:
```js
		var startPos = tabs.length - items.length; // Pinned tabs aren't displayed in menu
		for (let i = startPos, maxi = tabs.length; i < maxi; i++)
		{
			items[i - startPos].style.marginLeft = tabs[i].getAttribute(this.kNEST)+'em';
		}
```
But using of built-in `tab` property is better, I think.