Browser implied authentication for 0.9.0

Unlike the version for 0.8.3, I was unable to test this against known-to-work applications.  This pull request is an alternative for #600 that was made against 0.8.3 -- and which was tested as a drop-in substitute against the todomvc application.

I suspect what you really are after is a patch to HEAD.  Let me know if that is the case, and I'll make another.  (Pull Requests are fairly new to me, and the constraints that github places on them are too.)