Update shadow-piercing selectors

[sinedied]

Since newer angular-cli version, a new shadow-piercing selector ::ng-deep is favored to use (see https://angular.io/guide/component-styles#deprecated-deep--and-ng-deep).

As the support for the deep selector will be removed from the web components specs v1, its future is uncertain even among the Angular framework emulated encapsulation mode, so maybe we will have to rethink the use cases where it was needed (mostly to style/fix other framework components like Ionic).