Feature Request: Push Members Down & Safe Delete Refactor

[bvoq]

The JetBrains team has added some crucial methods for improving code refactors with introducing ReSharper into Kotlin, but also into the C# and Java world.

Whenever you enter a codebase that has the following code smells, push members down/safe delete is very useful:
Speculative generality: https://refactoring.guru/smells/speculative-generality
Deep Hierarchy: Having classes that extend other classes that extend other classes ...

With push members down, you can remove methods and fields from a class and push them to their subclasses respectively. Safe delete does the same thing but in addition deletes the intermediate class.

Maybe add the refactor here: Requests for Dart refactorings