Inline "select new contact" entry in picker

Removed the FAB now that we have a better way to create
new entries inside the contact picker.

Contacts: Created HeaderEntryContactListAdapter class that
overrides an adapter defined in ContactsCommon.

Part 3/3

Manual testing:
-verify dialer still builds, and displays its "Add to
 contacts" button correctly
-test rotation in contact picker
-Open intents in Contacts Intents app for legacy/non-legacy
 picker types. Verify they behave similarly
-perform a search inside the contact picker, and
 watch the "Add to contacts" entry vanish. (In my version of the framework
 SearchView is broken, so I needed to do this manually)
-remove accounts, and verify that both contact picker
 and legacy contact picker don't crash

Bug: 16209705
Change-Id: I1bafc557aa9cdae776fbfcc73aac3607a7bebe3e