In the DI DOCs the 'why' given for the component injector tree is to get multiple instances of a dependency. The editor component explicitly provides RestoreService
to ensure it gets its own instance.
providers instance of `RestoreService`
rootInjector [provide(RestoreService)] instance A
- heroEditorComponentInjector [provide(RestoreService)] instance B
- childOfHero [] instance B
- someOtherEditor [] instance A