Fix (sometimes serious) performance problem on submitting profiles for specified...

Fix (sometimes serious) performance problem on submitting profiles for specified contacts.

->_id is set when the contact id is known - e.g in edit, in contactlayouteditor profile
blocks. However, current logic still retrieves duplicates and then... does nothing
with them if ->_id is set. By moving the if up higher we can save the server from
doing unnecesary queries. Note that if you submit a tag profile with no other fields in it
the query is server-destroyingly bad with this