Merge "HWC2: Clarify null client target handle" into nyc-dev am: 0154a6b08d
am: b5e8a61c83

* commit 'b5e8a61c83e6cfe2850d0fc2c4ed61770ef87577':

Change-Id: I378a940e556c9f50a623659b8f88aa9275196fbb