Patch $browser for compatibility with Angular 1.3 $location changes

Angular 1.3 introduces a breaking change to $location, specifically requiring a baseHref to be present. Angular-mocks was patched with a similar change recently, but since angular-specs doesn't redefine $browser, the solution here is a little different. My solution is partially based off of the changes made in https://github.com/tbosch/angular.js/commit/607708e981a7e35e5b35eec69bcf592050949ad7.

Other relevant links:
https://docs.angularjs.org/error/$location/nobase
https://github.com/angular/angular.js/issues/8866

I'm not sure I have the most elegant solution, but at least the tests are running again :)