LPS-51831 - Documents and media portlet scoped to a page: if the first uploaded file is dragged, it will appear in the site scope as well

Hi Jon,

Attached is an update for https://issues.liferay.com/browse/LPS-51831.

I had to fire a new event from the portlet configuration portlet called 'scopeChange'.  So that the Documents & Media portlet could destroy the current instance of the uploader when the scope changes.

Please let me know if there are any issues.

Thanks!