SupportLeanbackShowcase: add Android.mk am: de41d1a459
am: 958d13b223

* commit '958d13b223ee591be6f6e74c5401d0f94ddbda8d':
  SupportLeanbackShowcase: add Android.mk

Change-Id: I89b630a9ce658f6dcbc16f6b459890374c3c1979