RFR[8238286]: 'Add new flatMap stream operation that is more amenable to pushing’

[Florian Weimer]

* Remi Forax:

> I still don't like the fact that IntMapMultiConsumer,
> DoubleMapMultiConsumer and LongMapMultiConsumer are not in
> java.util.function unlike all other functional interfaces used by
> the Stream API.

They seem rather too specific for java.util.function to me.  Maybe we
should add BiIntObjectConsumer etc., a BiConsumer whose first argument
is fixed as an int?  And the second consumer would be injected as a
type parameter, specific to the use in IntStream?