Implement MemberName interning.
There's a problem with initializing MemberNames.
MethodHandles::init_method_MemberName stores a reference to corresponding MemberName in InstanceKlass's MemberNameTable:
But it's possible to create multiple MemberName instances for the same method and previously stored reference is overwritten.
It can lead to problems (like JDK-8023004) during class redefinition.
Interning of MemberName instances should solve the problem.