RFR 8192864: defmeth tests can hide failures

[Harold David Seigel]

Hi,

Please review this small fix for JDK-8192864.  The fix was suggested in 
the bug.  It ensures that a defmeth test that gets an 
InvocationTargetException fails.  The fix was tested by temporarily 
adding throws of NullPointerExceptions to methods redefineClass() and 
retransformClass() in classes vm.runtime.defmeth.shared.Util, and making 
sure that the tests did not pass.

Open Webrev: 
http://cr.openjdk.java.net/~hseigel/bug_8192864/webrev/index.html

JBS Bug:  https://bugs.openjdk.java.net/browse/JDK-8192864

The fix was tested on Linux X64, Windows, Solaris, and Mac.

Thanks, Harold