fix($browser): prevent infinite $digest from no trailing slash in IE9

[hamfastgamgee]

fix($browser): prevent infinite $digest from no trailing slash in IE9

This fix prevents IE9 from throwing an infinite $digest error when the user accesses the base
URL of the site without a trailing slash. Suppose you owned http://www.mysite.com/app
and had an Angular app hosted in a subdirectory "app". If an IE9 user accessed
http://www.mysite.com/app infinite $digest errors would be thrown on the console, but the app
itself would eventually resolve properly and work fine. Now the infinite $digest errors will
not be thrown.

Closes #11439

[hamfastgamgee]

I've been unable to successfully make a unit test that exercises this problem. Part of that is that I'm still inexperienced with Jasmine, but part is also that the $browser mock does not actually expose the issue because it just sets its internal $$url property without doing all of the reloadLocation stuff.

[hamfastgamgee]

Well, there are tests attached now, but I'm not sure how accurately they actually represent the problem. :)

Also, you'll notice the error about some of the tests causing a page reload. I'm not at all sure how to avoid that (if it's even possible), given the problem can't be reproduced using $location calls due to the necessity of dropping the slash from the end of the base URL.