adapt_framework: doesn't always prevent buttons with aria-disabled from being clicked

[moloko]

If the button contains an inner element - for example a <div> wrapping the text label - clicking that element will trigger the button's click event anyway.

Need to amend this function to get it to check parents as well.

Additionally, that code doesn't seem to be initialising during the initial display of the language picker. Might be easiest just to change those to use the disabled attribute since I don't think it's really the end of the world if screenreader users are unaware of the existence of languages that aren't yet available.