We import Angular a11y CDK like so:
import { FocusableOption, FocusKeyManager } from '@angular/cdk/a11y';
It also imports all of the other a11y features, even those that we don't need yet. Is there a way to import just what we need? Tried importing from @angular/cdk/a11y/key-manager/ or something equivalent. Are we going against the grain here by not importing from public-api?
