This adds the ability to promote private fields to public ones to enable layoutlib to access them. This was first added in changeb556decf75, but reverted in847b0d3ad2. This is essentially a revert of the change again, but without the SimpleMonthView related stuff. Also, promote the Choreographer's field as is needed to support animations. Change-Id: Iee45a465c7a1cadd362c1841385941e6232e4900