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

This reverts commit 5e37b2a7fd0b837fdab97bb3525dabefc0ea848a.
Eagerly loading `$route`, could break tests, because it might request the root or default route
template (something `$httpBackend` would know nothing about).

It will be re-applied for `v1.6.x`, with a breaking change notice and possibly a way to disable
the feature is tests.

Fixes #14337