Br fixes

[briri]

Consolidates some redundant code in the typeahead controller.

@jupiter007 I noticed one remaining (and hopefully easy to fix) issue when testing all of the changes again:

• open a plan on the DMP uploads dashboard and go to the contributors page
• Edit the contributor that is marked as the primary contact
• Uncheck the primary contact box and save
• Then click 'Save and Continue'

It properly shows the error message now, but the contributor disappears from the list. If I refresh the page, the contributor is still there, so it's just a visual issue. This might cause the user to think that the contributor was deleted though and they may try to re-add them.

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