jquery/jquery-ui — pull request #1255 by safareli (2014-05-27 12:28:04+00:00)
Title: clear `previous` and `term` after changing source

`previous` and `term` should be cleared after changing source data.
reason:
user enters 'a' in input and autocomplete displays pup up;
inputs data source is changed;
inputs value is cleared by $element.val('');
user enters 'a' again and autocomplete doesn't displays pup up because `term` is not cleared;