Fix bugs in hi-res contact support.

Serialize updated photos and restore them upon device rotation; this
addresses bug 5999990.

Also, be sure to clear updated-photo entry when the user chooses
to remove the photo; otherwise it will still be saved when the user
exits the ContactEditorFragment via Back/"Done".  This wasn't yet
reported as a bug.

Bug: 5999990
Change-Id: I9a01d4b9e40fec0e764156271a292588ed1b7154