8229822: ThrowingPushPromises tests sometimes fail due to EOF

[Daniel Fuchs]

Hi,

Please find below a fix for:

8229822: ThrowingPushPromises tests sometimes fail due to EOF
https://bugs.openjdk.java.net/browse/JDK-8229822

While trying to write a good test for JDK-8245462 I stumbled
on two issues - which I believe are at the root of the
ThrowingPushPromises failures:

   - SocketTube: I found an issue where the scheduler might not
        be restarted if resuming/pausing event from within
        the scheduler loop (that runs in the selector manager
        thread) failed due to the socket being asynchronously
        closed by another thread.
        That could cause some tests to fail in timeout.

    - Http2Connection/Stream: there was an issue where DataFrames
        could be sent after a ResetFrame was sent. That caused the
        server to close down the connection. The next test would
        start opening a new stream on the same connection while
        the server was concurrently closing it, and the test
        would eventually fail - sometimes with a message saying
        "EOF reached while reading".

The webrev below includes these two fixes; The test have simply been
update to list 8229822 for verification purposes.

webrev:
http://cr.openjdk.java.net/~dfuchs/webrev_8229822/webrev.00/

best regards,

-- daniel