SupportLeanbackShowcase: add Android.mk am: de41d1a459
am: 2f1ccf605a

* commit '2f1ccf605a11bb363d2ee08445bf3e911ecc9c17':
  SupportLeanbackShowcase: add Android.mk

Change-Id: I52bea7d5987a5eb7a2ffddda31067ec01ef66066