RFR: JDK-8205549 JDK-8205698 Support of flattened values in Unsafe

[Paul Sandoz]

> This also reminds me that we need a way to use Unsafe
> to patch value instance fields.  Here's how I would like to
> do this, as a first cut:
> 

That’s a good observation. The lack of enforcement on Unsafe allow us to internally break the rules (as long as the intermediate breaking effects are contained and cannot be observed externally). I can see interesting usages for object + fused tail and writing values to that tail, or even perhaps scribbling values that contain no oops to a byte buffer.

Paul.