RFR (14) 8236779: static field in implementation class erroneously leaking in memory access javadoc

[Maurizio Cimadamore]

Please review this one liner, which is to fix a static implementation 
field leaking through the memory access API javadoc:

cr.openjdk.java.net/~mcimadamore/8236779

And corresponding CSR here:

https://bugs.openjdk.java.net/browse/JDK-8236780

Cheers
Maurizio