RFR: 8165492: Reduce number of lambda forms generated by MethodHandleInlineCopyStrategy

[Vladimir Ivanov]

> Webrev: http://cr.openjdk.java.net/~redestad/8165492/webrev.01/

Looks good.

As others, I prefer InternalError over IllegalStateException when buffer 
size mismatch.

Best regards,
Vladimir Ivanov


> Testing: RBT, no regressions observed on microbenchmarks[1], while
> recuperating ~25-30% of the largest startup regressions introduced in
> 9+120
>
> It's not the intent of this change to make this new foldArguments a
> part of the public API, since it's simply too late for 9. Instead we'd
> like to defer the discussion of possibly including this in the public
> API until a later time, which also gives us ample opportunity to
> examine other options - such as being better at not fully generating
> intermediary LFs.
>
> Thanks!
>
> /Claes