I don't think there is a ```$scope``` mock.  If you try replacing everything with ```$scope``` you get:
```
	Error: Unknown provider: $scopeProvider <- $scope
```
in all the tests.  I could do something like this if you preferred:
```javascript
        inject(function(_$compile_, _$rootScope, _$httpBackend_) {
            $compile = _$compile_;
            $scope = _$rootScope;
            $httpBackend = _$httpBackend_;
        });
```
Although that isn't as descriptive.