surfaceflinger: hwc1: Add missing mActiveFrameSequence counter

In commit 66a7233a,
the mActiveFrameSequence counter was not ported to
HWC1, causing the blur layer to not capture any
screenshot after the initial one.

The end result is a static blur image that never changes.

Add the missing counter so that blur screenshots
get re-captured when needed.

Change-Id: I97294d11821297217853bb7ff2d11de475d98325