Doc: Fix documentation warnings for Qt GUI

* Drop deprecation warnings for now-dropped items
* Use the 'qt6' define and a new \nothing doc macro to conditionally
  document items on Qt 6
* Add a custom module header for docs that pulls in also Vulkan headers
* Add \internal command for internal classes/functions
* Move QtGUI-related code snippets from widgets to gui docs

Change-Id: Ieb386b96631a49568d09059906d307c45c01d93a
Reviewed-by: Paul Wicking <paul.wicking@qt.io>

3 files changed, 0 insertions, 243 deletions

diff --git a/src/widgets/doc/snippets/code/src_gui_kernel_qaction.cpp b/src/widgets/doc/snippets/code/src_gui_kernel_qaction.cpp
deleted file mode 100644
index 763238076c..0000000000
--- a/src/widgets/doc/snippets/code/src_gui_kernel_qaction.cpp
+++ /dev/null
@@ -1,59 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the documentation of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:BSD$
-** Commercial License Usage
-** Licensees holding valid commercial Qt licenses may use this file in
-** accordance with the commercial license agreement provided with the
-** Software or, alternatively, in accordance with the terms contained in
-** a written agreement between you and The Qt Company. For licensing terms
-** and conditions see https://www.qt.io/terms-conditions. For further
-** information use the contact form at https://www.qt.io/contact-us.
-**
-** BSD License Usage
-** Alternatively, you may use this file under the terms of the BSD license
-** as follows:
-**
-** "Redistribution and use in source and binary forms, with or without
-** modification, are permitted provided that the following conditions are
-** met:
-**   * Redistributions of source code must retain the above copyright
-**     notice, this list of conditions and the following disclaimer.
-**   * Redistributions in binary form must reproduce the above copyright
-**     notice, this list of conditions and the following disclaimer in
-**     the documentation and/or other materials provided with the
-**     distribution.
-**   * Neither the name of The Qt Company Ltd nor the names of its
-**     contributors may be used to endorse or promote products derived
-**     from this software without specific prior written permission.
-**
-**
-** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
-
-//! [0]
-QApplication app(argc, argv);
-app.setAttribute(Qt::AA_DontShowIconsInMenus);  // Icons are *no longer shown* in menus
-// ...
-QAction *myAction = new QAction();
-// ...
-myAction->setIcon(SomeIcon);
-myAction->setIconVisibleInMenu(true);   // Icon *will* be shown in menus for *this* action.
-//! [0]
diff --git a/src/widgets/doc/snippets/code/src_gui_kernel_qshortcut.cpp b/src/widgets/doc/snippets/code/src_gui_kernel_qshortcut.cpp
deleted file mode 100644
index bac264fcfc..0000000000
--- a/src/widgets/doc/snippets/code/src_gui_kernel_qshortcut.cpp
+++ /dev/null
@@ -1,65 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the documentation of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:BSD$
-** Commercial License Usage
-** Licensees holding valid commercial Qt licenses may use this file in
-** accordance with the commercial license agreement provided with the
-** Software or, alternatively, in accordance with the terms contained in
-** a written agreement between you and The Qt Company. For licensing terms
-** and conditions see https://www.qt.io/terms-conditions. For further
-** information use the contact form at https://www.qt.io/contact-us.
-**
-** BSD License Usage
-** Alternatively, you may use this file under the terms of the BSD license
-** as follows:
-**
-** "Redistribution and use in source and binary forms, with or without
-** modification, are permitted provided that the following conditions are
-** met:
-**   * Redistributions of source code must retain the above copyright
-**     notice, this list of conditions and the following disclaimer.
-**   * Redistributions in binary form must reproduce the above copyright
-**     notice, this list of conditions and the following disclaimer in
-**     the documentation and/or other materials provided with the
-**     distribution.
-**   * Neither the name of The Qt Company Ltd nor the names of its
-**     contributors may be used to endorse or promote products derived
-**     from this software without specific prior written permission.
-**
-**
-** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
-
-//! [0]
-shortcut = new QShortcut(QKeySequence(tr("Ctrl+O", "File|Open")),
-                         parent);
-//! [0]
-
-
-//! [1]
-setKey(0);                  // no signal emitted
-setKey(QKeySequence());     // no signal emitted
-setKey(0x3b1);              // Greek letter alpha
-setKey(Qt::Key_D);              // 'd', e.g. to delete
-setKey('q');                // 'q', e.g. to quit
-setKey(Qt::CTRL + Qt::Key_P);       // Ctrl+P, e.g. to print document
-setKey("Ctrl+P");           // Ctrl+P, e.g. to print document
-//! [1]
diff --git a/src/widgets/doc/snippets/code/src_gui_util_qundostack.cpp b/src/widgets/doc/snippets/code/src_gui_util_qundostack.cpp
deleted file mode 100644
index 8f59fe9cb3..0000000000
--- a/src/widgets/doc/snippets/code/src_gui_util_qundostack.cpp
+++ /dev/null
@@ -1,119 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the documentation of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:BSD$
-** Commercial License Usage
-** Licensees holding valid commercial Qt licenses may use this file in
-** accordance with the commercial license agreement provided with the
-** Software or, alternatively, in accordance with the terms contained in
-** a written agreement between you and The Qt Company. For licensing terms
-** and conditions see https://www.qt.io/terms-conditions. For further
-** information use the contact form at https://www.qt.io/contact-us.
-**
-** BSD License Usage
-** Alternatively, you may use this file under the terms of the BSD license
-** as follows:
-**
-** "Redistribution and use in source and binary forms, with or without
-** modification, are permitted provided that the following conditions are
-** met:
-**   * Redistributions of source code must retain the above copyright
-**     notice, this list of conditions and the following disclaimer.
-**   * Redistributions in binary form must reproduce the above copyright
-**     notice, this list of conditions and the following disclaimer in
-**     the documentation and/or other materials provided with the
-**     distribution.
-**   * Neither the name of The Qt Company Ltd nor the names of its
-**     contributors may be used to endorse or promote products derived
-**     from this software without specific prior written permission.
-**
-**
-** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
-
-//! [0]
-class AppendText : public QUndoCommand
-{
-public:
-    AppendText(QString *doc, const QString &text)
-        : m_document(doc), m_text(text) { setText("append text"); }
-    void undo() override
-        { m_document->chop(m_text.length()); }
-    void redo() override
-        { m_document->append(m_text); }
-private:
-    QString *m_document;
-    QString m_text;
-};
-//! [0]
-
-
-//! [1]
-MyCommand *command1 = new MyCommand();
-stack->push(command1);
-MyCommand *command2 = new MyCommand();
-stack->push(command2);
-
-stack->undo();
-
-MyCommand *command3 = new MyCommand();
-stack->push(command3); // command2 gets deleted
-//! [1]
-
-
-//! [2]
-QUndoCommand *insertRed = new QUndoCommand(); // an empty command
-insertRed->setText("insert red text");
-
-new InsertText(document, idx, text, insertRed); // becomes child of insertRed
-new SetColor(document, idx, text.length(), Qt::red, insertRed);
-
-stack.push(insertRed);
-//! [2]
-
-
-//! [3]
-bool AppendText::mergeWith(const QUndoCommand *other)
-{
-    if (other->id() != id()) // make sure other is also an AppendText command
-        return false;
-    m_text += static_cast<const AppendText*>(other)->m_text;
-    return true;
-}
-//! [3]
-
-
-//! [4]
-stack.beginMacro("insert red text");
-stack.push(new InsertText(document, idx, text));
-stack.push(new SetColor(document, idx, text.length(), Qt::red));
-stack.endMacro(); // indexChanged() is emitted
-//! [4]
-
-
-//! [5]
-QUndoCommand *insertRed = new QUndoCommand(); // an empty command
-insertRed->setText("insert red text");
-
-new InsertText(document, idx, text, insertRed); // becomes child of insertRed
-new SetColor(document, idx, text.length(), Qt::red, insertRed);
-
-stack.push(insertRed);
-//! [5]