SurfaceView: Avoid over-reporting DRAW_FINISHED.

To some extent we rely on the app to call the draw callback
if they want the app to work properly, but this case is fairly easy
to detect, so why not prevent it and provide a helpful log.

Bug: 62051758
Test: Warm start camera a few times. go/wm-smoke.
Change-Id: I39f4e015bfa15a1e0c37dba70b4a700803a6a274