Steps:
1) Open a new tab.
2) Load cnn.com
3) Load thestar.com (by typing the URL in the URL bar)

The back button is grayed out, but we should be able to go back to cnn.com.

Continuing to navigate to other URLs (by typing in the URL bar), it seems that we sometimes get an active back button and sometimes not.

Navigating by tapping on links works properly though.

I'm not sure if this corresponds to any unit test failure.