Move MDI example to manual test

Pick-to: 6.5 6.6
Change-Id: Ide698a171a4600cb4bac6574b6be74c17f779051
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

examples/widgets/doc/src/mdi.qdoc

@@ -1,14 +0,0 @@
-// Copyright (C) 2016 The Qt Company Ltd.
-// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
-
-/*!
-    \example mainwindows/mdi
-    \title MDI Example
-    \ingroup examples-mainwindow
-
-    \brief The MDI example shows how to implement a Multiple Document Interface using Qt's
-    QMdiArea class.
-
-    \image mdi-example.png
-
-*/

examples/widgets/mainwindows/CMakeLists.txt

@@ -2,5 +2,4 @@
 # SPDX-License-Identifier: BSD-3-Clause
 
 qt_internal_add_example(mainwindow)
-qt_internal_add_example(mdi)
 qt_internal_add_example(menus)

examples/widgets/mainwindows/mainwindows.pro

@@ -1,4 +1,3 @@
 TEMPLATE      = subdirs
 SUBDIRS       = mainwindow \
-                mdi \
                 menus

examples/widgets/tutorials/notepad/gettingstartedqt.qdoc

@@ -486,10 +486,6 @@
         \header
             \li About
             \li Here
-        \row
-            \li MDI applications
-            \li QMdiArea,
-               \l{MDI Example}
         \row
             \li Files and I/O devices
             \li QFile, QIODevice

src/widgets/kernel/qwidget.cpp

@@ -11543,7 +11543,7 @@ void QWidgetPrivate::setWindowOpacity_sys(qreal level)
     its parent because other children of the parent might have been
     modified.
 
-    \sa windowTitle, {MDI Example}
+    \sa windowTitle
 */
 bool QWidget::isWindowModified() const
 {

src/widgets/widgets/qmainwindow.cpp

@@ -281,7 +281,7 @@ void QMainWindowPrivate::init()
     of the toolbars and dock widgets that are stored.
 
     \sa QMenuBar, QToolBar, QStatusBar, QDockWidget,
-    {MDI Example}, {Menus Example}
+    {Menus Example}
 */
 
 /*!