[API Review]: RT-28289 Unable to determine the selected ExtensionFilter when a FileChooser closes

[Richard Bair]

> I have only one minor comment:
>> in the list of selection filters
> Should I read this as extension filters?

Yes thanks!

>> I don't think we should be clearing the selectedExtensionFilter if the dialog has been cancelled.
> It was intended as extra check for cancelled dialog, but you are right, it's unnecessary.

Good, lets fix that and then I think we're good to go.

Richard