Allow Secure Transport backend to use a temporary keychain

Cherry picked:

this change was first merged into dev, but now we also need it in 5.9
to enable SSL socket tests on the new CI VMs (macOS 10.11, 10.12).
As we do not merge dev->5.9, we need this cherry-pick.

Since day one Secure Transport socket has two annoying problems on macOS:
when we call SecPKCS12Import, we indeed import certs and keys into the default keychain
and also (which is more serious) later a dialog can pop up, asking for permission
to use a private key (this is especially annoying if you're running SSL autotests or
have a server application). Apparently, it's possible to work around those problems
if we create our own (temporary) keychain and pass it in the 'options' parameter
to SecPKCS12Import.

[ChangeLog][QtNetwork] Allow QSslSocket to use a temporary keychain on macOS.

Task-number: QTBUG-56102
Change-Id: Ic3a56c905100dc80d907a25fe6ebfa232dcf5b9e
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
(cherry picked from commit 17927392cf1cecb20cef7cb9cd77131391de087c)
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>

0 files changed, 0 insertions, 0 deletions