fix(ngRoute): allow `ngView` to be included in an asynchronously loaded template

During it's linking phase, `ngView` relies on the info provided in `$route.current` for
instantiating the initial view. `$route.current` is set in the callback of a listener to
`$locationChangeSuccess`, which is registered during the instantiation of the `$route` service.

Thus, it is crucial that the `$route` service is instantiated before the initial
`$locationChangeSuccess` is fired. Since `ngView` declares `$route` as a dependency, the service is
instantiated in time if `ngView` is present during the initial load of the page.

Yet, in cases where `ngView` is included in a template that is loaded asynchronously (e.g. in
another directive's template), the directive factory might not be called soon enough for `$route`
to be instantiated before the initial `$locationChangeSuccess` event is fired.

This commit fixes it, by always instantiating `$route` up front, during the initialization phase.

Fixes #1213
Fixes #6812

Closes #14088