RFR(S) 8028319 - ConflictingDefaultsTest.testReabstract spins when running with -mode invoke and -Xcomp

[Morris Meyer]

Could I get a review for this bug?

This issue with the defmethod test stems from the invalidation of an 
abstract method invocation from invokehandle.   This comment for the 
_abstract_method_handler (now changed) pointed out the issue.

   // Create a special handler for abstract methods.  Abstract methods
   // are never compiled so an i2c entry is somewhat meaningless, but
   // fill it in with something appropriate just in case.  Pass handle
   // wrong method for the c2i transitions.

Many thanks to Vladimir Ivanov and John Rose in helping to track this 
one down.  Vladimir has tested this through JPRT as well as VM testbase 
+ HS/JDK regression in Aurora over the weekend.

         --morris

WEBREV - http://cr.openjdk.java.net/~morris/8028319


JBS - https://bugs.openjdk.java.net/browse/JDK-8023500 duplicate 8028319 
- added here for background
JBS - https://bugs.openjdk.java.net/browse/JDK-8028319