Implementation delegation of inherited interfaces

Language Design
1

Suppose we have next interface:

interface TabsInfo : Iterable<Tab>

Then we can not write:

class TabsBuilder(
    private val tabs: Iterable<Tab> = mutableListOf()
) : TabsInfo by tabs {
    //...other code
}

I understand why. Because TabsInfo can extend Iterable by introducing new methods.
But apparently we can write:

class TabsBuilder(
    private val tabs: Iterable<Tab> = mutableListOf()
): TabsInfo, Iterable<Tab> by tabs {
   //...other code
}

So in general it is possible to provide delegation pattern for inherited interfaces.
The question is: is it planned or maybe is there a wish to plan supporting of delegation by for inherited interfaces, so first example will be acceptable. For example, if TabsInfo had additional method, then we need to implement it in TabsBuilder according to first and second examples, but we will not need to specify additional interface in TabsBuilder class declaration like in second example.Preformatted text