When a property backed by a final field is the delegate for interface
implementation by delegation, the backend should reuse the backing
field rather than introduce a new, extraneous `$$delegate_n` field.
This patch mutes the following test categories:
* Tests with java dependencies (System class,
java stdlib, jvm-oriented annotations etc).
* Coroutines tests.
* Reflection tests.
* Tests with an inheritance from the standard
collections.
Kristoffer Andersen