Network: Fix up previous corruption patch

[Timo Jyrinki]

(https://codereview.qt-project.org/#/c/120738)

Committed to all Qt stable series:

This is a fix-up for cff39fba10ffc10ee4dcfdc66ff6528eb26462d3.
That patch lead to some internal state issues that lead to the QTBUG-47048
or to QNetworkReply objects erroring with "Connection Closed" when
the server closed the Keep-Alive connection.

This patch changes the QNAM socket slot connections to be DirectConnection.
We don't close the socket anymore in slots where it is anyway in a closed state
afterwards. This prevents event/stack recursions.
We also flush QSslSocket/QTcpSocket receive buffers when receiving a disconnect
so that the developer always gets the full decrypted data from the buffers.

[ChangeLog][QtNetwork] Fix HTTP issues with "Unknown Error" and "Connection Closed"
[ChangeLog][QtNetwork][Sockets] Read OS/encrypted read buffers when connection
closed by server.

[Launchpad Janitor (janitor)]

This bug was fixed in the package qtbase-opensource-src - 5.4.2+dfsg-2ubuntu6

---------------
qtbase-opensource-src (5.4.2+dfsg-2ubuntu6) wily; urgency=medium

  * debian/patches/stale-process-lock.patch:
    - Fix QLockFile not noticing if the lock pid is re-used by unrelated
      process (LP: #1500444)

 -- Timo Jyrinki <email address hidden> Tue, 29 Sep 2015 07:18:23 +0000