Angular org unit selector should open focused on current selection

[Andrea Neiman]

This came out of testing for the Hopeless Holds work (bug 1811710), which is on recent master (3.3+).

If your current selected org unit is in the middle of the selector list, and you click in the dropdown to change the selection, you are placed at the top of the org unit list. It would be better behavior to have the list focused at the current selection, wherever it is in the list.

(note that I can see an argument for having it default to the top of the list, so I'm adding the needsdiscussion tag).