If we get an error in the Watch loop, it will send this on awsChan,
which will cause Watch to loop. However, in this scenario it will never
cause closeChan to close, and we will deadlock because we have a
waitGroup in a helper goroutine which is waiting on this channel to
close the context.
Normally this wouldn't be an issue, but since we have more than one
goroutine (with associated waitGroup) it is. It's also good practice to
close all the channels to help avoid this kind of bug.
This patch also moves the waitGroup Wait into a more logical place for
visibility.
