skip capture conversion before subtyping if types are parameterizations of the same class or interface

FULL PRODUCT VERSION :
java version "9-ea"
Java(TM) SE Runtime Environment (build 9-ea+121)
Java HotSpot(TM) 64-Bit Server VM (build 9-ea+121, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Darwin snazy-ds15.local 15.5.0 Darwin Kernel Version 15.5.0: Tue Apr 19 18:36:36 PDT 2016; root:xnu-3248.50.21~8/RELEASE_X86_64 x86_64


A DESCRIPTION OF THE PROBLEM :
Apache Cassandra fails to compile o.a.c.utils.Throwables at line #79.

https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/utils/Throwables.java#L79

The relevant methods look like this:

    public static <E extends Exception> void perform(DiscreteAction<? extends E> ... actions) throws E
    {
        perform(Stream.of(actions));
    }
    public static <E extends Exception> void perform(Stream<DiscreteAction<? extends E>> actions) throws E
    {
        ...
    }

The above compiles fine w/ JDK8 but fails with JDK9.

As a workaround, I've changed the invocation to "Throwables.<E>perform(Stream.of(actions));"

(FYI: Got a branch that compiles fine working around that issue here: https://github.com/snazy/cassandra/tree/9608-java9-trunk)

REGRESSION. Last worked in version 8u92

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Checkout Apache Cassandra using current trunk & run "ant jar"


REPRODUCIBILITY :
This bug can be reproduced always.

CUSTOMER SUBMITTED WORKAROUND :
(see above)