CdkPortalOutlet should resolve componentFactories through the portal's ComponentFactoryResolver

Bug, feature request, or proposal:

At the moment, CdkPortal tries to resolve ComponentFactories via its own CFR which it got from its own Injector instance:

const componentFactory = this._componentFactoryResolver.resolveComponentFactory(portal.component);

It may happen that you’d like to attach a ComponentPortal with a lazily loaded entryComponent that’s not resolvable through the PortalHost's CFR. It should then try to get a CFR instance from the Portal to resolve the ComponentFactory if it can’t resolve it through its own:

const componentFactory = portal.injector.get(ComponentFactoryResolver).resolveComponentFactory(portal.component);

I’m not sure if this has any negative side effects.

[jelbourn]

That’s a good point; you’d want the resolver to be associated with the ComponentPortal in that case. That makes more sense anyway, since TemplatePortal doesn’t use the resolver at all. The simplest thing would probably be adding a ComponentFactoryResolver as a 4th argument to the constructor for ComponentPortal. I would shy away from trying to get it from the given injector because someone might want to use an injector from a totally different part of the application tree.

[j2L4e]

@crisbeto you closed the linked PR stating that this wouldn’t be necessary in Angular 6+. Could you elaborate on how resolving factories has changed?

Thank you for your work!