RFR [9] 8157045: NPE during websocket communication with wss

[Chris Hegarty]

8157045 [1] is blocking folks doing test development for WebSockets. I would
like to push this “temporary” change, to unblock them, until we can refactor some
of this area to fix what appears to be a more significant issue ( readImpl(ByteBuffer)
can read bytes into a different ByteBuffer, but has no way of communicating that
to the caller ). I added asserts to catch this, for now.

http://cr.openjdk.java.net/~chegar/8157045/

-Chris.

[1] https://bugs.openjdk.java.net/browse/JDK-8157045