RFR: 8221984: Clean up ZOop

[Erik Osterlund]

+1

/Erik

> On 4 Apr 2019, at 14:51, Per Liden <per.liden at oracle.com> wrote:
> 
> Mainly renaming ZOop::to_oop() to ZOop::from_address(), but also turning ZOop into a pure cast utility class. The other functions in this class weren't widely used.
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8221984
> Webrev: http://cr.openjdk.java.net/~pliden/8221984/webrev.0
> 
> /Per