switchMap does not seem to complete when the inner observable completes
<p>I'm still a noob when it comes to RxJS but here's a JSBin of what I am trying to do.</p>

<p><a href="https://jsbin.com/wusalibiyu/1/edit?js,console" rel="noreferrer">https://jsbin.com/wusalibiyu/1/edit?js,console</a></p>

<p>I have an observable 'a' (in my case it's the current active connection) which emits a new object whenever the connection reconnects. It's an observable itself because it can re-emit a new value.</p>

<p>I now want an observable that completes whenever an action is executed on the current connection. That action notifies it is done when the observable for it completes. This is b.</p>

<p>The problem is that when the inner observable completes, the outer does not complete. How to make the outer observable complete ... . Is there a different operator I should be using in RxJS5?</p>