8158169: MethodHandles.dropArgumentsToMatch(...)
Reviewed-by: psandoz, mhaupt

8158171: MethodHandles.dropArgumentsToMatch(...) non-documented IAE
Reviewed-by: sundar, mhaupt

8150829: Enhanced drop-args, identity and default constant, varargs adjustment
Reviewed-by: psandoz, mhaupt, jrose