Liststyle adds Bulleted List Properties to context menu for an editor with no content

[nikmaslik]

Steps to reproduce

1. Wrap CKEditor in ul tag like this <ul><li><div contenteditable="true" /></li></ul>
2. Add Liststyle plugin to the editor
3. Open the the page with CKEditor , observe context menu

Expected result

No Bulleted List Properties in the menu

Actual result

Bulleted List Properties is in the menu

Other details (browser, OS, CKEditor version, installed plugins)

This is a coding error. Liststyle adds Bulleted List Properties to the context menu when the current element has ul or ol ancestors. With current code, the search goes outside of CK editor and finds ul or ol. The search should stop once it reaches the editor element.