[8u20] RFR Backport of JDK-8037806: constraint on multianewarray instruction is not checked since class version 50

[Lois Foltan]

Please approve the backport of JDK-8037806 to jdk8u.  The changeset 
applied cleanly.

The bug:
https://bugs.openjdk.java.net/browse/JDK-8038076

The webrev:
http://cr.openjdk.java.net/~lfoltan/bug_jdk8038076_8u/

The jdk9 changeset:
http://hg.openjdk.java.net/jdk9/hs-rt/hotspot/rev/8196842abf5c

Thanks,
Lois