SurfaceView: Ensure position update listener sets at least once

If we destroy and recreate a SurfaceView in the same frame its
possible for positionChanged for the new surface to arrive
before positionLost for the old surface. In this case we
won't clear mRtLastReportedPosition, and so we won't set
any position at all on the new surface.

Bug: 229052731
Test: Existing tests pass
Change-Id: I896496afa5b05848f96b20697d33911cae9639a7