Display issue with selectize theme + multiple + required #1889
Description
Not sure that this is the same as previous issues with ui-select + multiple + required (eg. #258).
Issue is that with <ui-select theme="selectize" multiple ng-required="true" ...> the control doesn't display the expected red 'invalid' border initially. Adding an item then removing it again then shows the red border.
It looks like it's related to the ng-dirty style against the created parent ui-select-container DIV. If you manually add that style in FF/Chrome devtools then the red border shows up.
See: http://plnkr.co/edit/Iqb6fx0LUqupBUIS3xIL?p=preview
Other similar issues such as #258 seem to relate to ng-empty or ng-invalid not being set, but devtools shows that these are correctly set here. This seems to be a styling thing.
Note also that with theme="bootstrap" even adding then removing items doesn't highlight the empty field. Maybe that's a different issue, but seems likely to be closely related.