Fix "Set default" in QuickContact

QuickContactActivity's context menu shows up "Set default" item even
when contact has only one phone number or email. Add back the logic
that checked whether there was only one of these. It was accidentally
removed in ag/6001361

Test: Verified single phone number and single email entries don't have
"Set default"

FIXES: 132227659
Change-Id: Ie08af672688eb1691107e9b19d73e09692dc433d