feat(Dialog): animate.leave

[ErsinCabuk]

Feature Description

When you use the if control flow or ViewContainerRef.createComponnt in Angular, animate.enter and animate.leave work. However, animate.leave support is not provided in components such as Dialog and Overlay. I think the reason is that the overlay is directly destroyed.

Use Case

Use case: https://stackblitz.com/edit/stackblitz-starters-trwgh2rt?file=package.json

[XhstormR]

maybe this is the reason #28878

[crisbeto]

We should handle this, but the problem is that there's no API that we can use to listen to when the animations are running. We work around this in the Material dialog by starting the animation and calling close only once it's done.