hwc: Fix request flag reset and Present() bailout
The ClearRequestFlags() method iterates over layer_stack_ instead of
layer_set_. This causes a use-after-free since DestroyLayer() removes
layer from layer_set_ only. Besides that, the method need not be
virtual and has a redundant loop. This change removes the
ClearRequestFlags() method and clears flags in an existing loop.
Present() bails out if layer_set_ is empty or a shutdown is pending.
Since layers could have been destroyed before Present(), ideally
bailing out on re-validation has a higher priority over the rest.
Change-Id: Ic7b31bbd07a22b8df47fccb2024b3415ab3a559b
CRs-fixed: 2165926
2 files changed
