RFR 8022887: Assertion hit while using class and redefining it with RedefineClasses s,imultaneously

[Coleen Phillimore]

Summary: Need to refetch the methods array from InstanceKlass after 
safepoint.

open webrev at http://cr.openjdk.java.net/~coleenp/8022887/
bug link at http://bugs.sun.com/view_bug.do?bug_id=8022887
Tested with the test cases in the bug, and with internal SQE tests 
(nsk.quick.testlist).

thanks,
Coleen