CRM-14470 - Prevent users from adding two fields of the same field type
(eg. phone) with location type 'is_primary'.
CRM-14470 - Moved check for existing field edits inside the function.
Merge pull request #3041 from freeform/CRM-14470

CRM-14470 - Prevent users from adding two 'is_primary' fields of the same field type