Summary
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Modify the SunJSSE implementation of the `SSLSocket shutdownInput()` method to not send a fatal alert to the peer and to not invalidate the TLS session if the SSLSocket hasn't received a close notification message from its peer.

Problem
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[This is a retroactive CSR for an issue which didn't go through the CSR process. A request to log one retrospectively has been made]

The old SunJSSE implementation of the `SSLSocket.shutdownInput()` method caused a fatal TLS alert to be generated and sent if the peer socket hadn't sent a `close_notify` message. This behavior was overly strict and not necessary according to the TLS RFCs. (see https://tools.ietf.org/html/rfc5246 - section 7.2.1)

Creating a fatal alert in such scenarios also has a performance impact given that the TLS session is invalidated. 

Solution
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If an application tries to close the input stream of an `SSLSocket` (via `shutdownInput()` method)  without having received a close notification message from its peer, the `SSLSocket` will no longer:

1.  trigger the transmission of a TLS fatal-level alert to the peer, and
2.  invalidate the current TLS session.	

The new behavior will still consider this condition an error and will throw a local `javax.net.ssl.SSLException`. A fatal-level alert will no longer be sent to the peer, and the underlying session will remain valid.

In addition, the internal transport context for the `SSLSocket` will also now be closed. Previously, this step didn't occur if a fatal message was generated.

Specification
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There are no API changes.  The patch for this change can be viewed via:

https://github.com/openjdk/jdk/commit/a4e082e9