Resolves: tdf#100732 hang closing Print Preview with X-icon on menubar

triggered by change...

commit f9bb13419549d621ffd55d9d81e0732a89560e2e
Author: Juergen Funk <juergen.funk_ml@cib.de>
Date:   Fri May 13 10:42:17 2016 +0200

    tdf#99815 use XNotifyingDispatch in sfx2

which allowed the problem introduced by...

commit d0c3c24da2506bff1719a276f2eff34589fa7663
Author: Kohei Yoshida <kohei.yoshida@gmail.com>
Date:   Wed Jun 6 01:28:55 2012 -0400

    Check if the system window has a close handler, and if yes, call it.

    This allows the close event in the preview window to be handled in a
    custom fashion, instead of having it call the normal "close window"
    command.

to show up

Change-Id: I5c46fb7a49ae44fd748b5b7192aeb951c7d65191
diff --git a/framework/source/dispatch/closedispatcher.cxx b/framework/source/dispatch/closedispatcher.cxx
index a09018f..aa15c28 100644
--- a/framework/source/dispatch/closedispatcher.cxx
+++ b/framework/source/dispatch/closedispatcher.cxx
@@ -186,6 +186,15 @@ void SAL_CALL CloseDispatcher::dispatchWithNotification(const css::util::URL&   
    {
        // The closing frame has its own close handler.  Call it instead.
        m_pSysWindow->GetCloseHdl().Call(*m_pSysWindow);

        aWriteLock.clear();
        // <- SAFE ------------------------------

        implts_notifyResultListener(
            xListener,
            css::frame::DispatchResultState::SUCCESS,
            css::uno::Any());

        return;
    }