RFR 8181292 Backport Rename internal Unsafe.compare methods from 10 to 9

[Mandy Chung]

> On Jun 1, 2017, at 8:56 AM, Paul Sandoz <paul.sandoz at oracle.com> wrote:
> 
> Hi,
> 
> To make it easier on 166 and Graal code to support both 9 and 10 we should back port the renaming of the internal Unsafe.compareAndSwap to Unsafe.compareAndSet:
> 
>  http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8181292-unsafe-cas-rename-jdk/webrev/
>  http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8181292-unsafe-cas-rename-hotspot/webrev/

Looks fine to me.  Just to mention - a few test/compiler/unsafe/SunMiscUnsafeAccessTestXXX.java tests only have the copyright header fix and it’s okay to backport them as it’s part of the JDK 10 changeset. 

Mandy