ActivityRecordInputSink: Ensure timely release of SurfaceControl

Relying on the garbage collector to release SurfaceControl and trigger
destruction of server-side layers has proven to be unreliable in
monkey testing. In this case it may cause the accumulation of
a large number of InputWindowInfo, leading to oneway binder spam.

Bug: 228810413
Test: Existing tests pass
Change-Id: If961767a1209674f202518f8b8be8f930d1a43e3