Shift iOS a11y translations into C++ file

lupdate cannot parse .mm files. Therefore tr markup must be inside of
C++ files. This copies the same approach qtconnectivity uses, see
6b2fd04b7be4494767b6092a030607010d91310c

Change-Id: I9853864b4b81b48da763a387c78c102857f23047
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>
Reviewed-by: Kai Koehne <kai.koehne@qt.io>
(cherry picked from commit c99849d0bc72df31ffde26c9ebffbf152cfcaeae)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

src/plugins/platforms/ios/CMakeLists.txt

@@ -27,6 +27,7 @@ qt_internal_add_plugin(QIOSIntegrationPlugin
         qioswindow.h qioswindow.mm
         quiaccessibilityelement.h quiaccessibilityelement.mm
         quiview.h quiview.mm
+        uistrings_p.h uistrings.cpp
     LIBRARIES
         ${FWAudioToolbox}
         ${FWFoundation}

src/plugins/platforms/ios/quiaccessibilityelement.mm

@@ -43,6 +43,7 @@
 
 #include "private/qaccessiblecache_p.h"
 #include "private/qcore_mac_p.h"
+#include "uistrings_p.h"
 
 QT_NAMESPACE_ALIAS_OBJC_CLASS(QMacAccessibilityElement);
 
@@ -117,7 +118,9 @@ QT_NAMESPACE_ALIAS_OBJC_CLASS(QMacAccessibilityElement);
     QAccessible::State state = iface->state();
 
     if (state.checkable)
-        return state.checked ? @"checked" : @"unchecked"; // FIXME: translation
+        return state.checked
+                ? QCoreApplication::translate(ACCESSIBILITY_ELEMENT, AE_CHECKED).toNSString()
+                : QCoreApplication::translate(ACCESSIBILITY_ELEMENT, AE_UNCHECKED).toNSString();
 
     QAccessibleValueInterface *val = iface->valueInterface();
     if (val) {

src/plugins/platforms/ios/uistrings.cpp

@@ -0,0 +1,51 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "uistrings_p.h"
+
+// Translatable messages should go into this .cpp file for them to
+// be picked up by lupdate.
+
+QT_BEGIN_NAMESPACE
+
+const char ACCESSIBILITY_ELEMENT[] = "quiaccessibilityelement";
+const char AE_CHECKED[] = QT_TRANSLATE_NOOP("quiaccessibilityelement", "checked");
+const char AE_UNCHECKED[] = QT_TRANSLATE_NOOP("quiaccessibilityelement", "unchecked");
+
+QT_END_NAMESPACE

src/plugins/platforms/ios/uistrings_p.h

@@ -0,0 +1,66 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef UISTRINGS_P_H
+#define UISTRINGS_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtCore/QCoreApplication>
+#include <QtCore/QString>
+
+QT_BEGIN_NAMESPACE
+
+// quiaccessibilityelement related strings
+extern const char ACCESSIBILITY_ELEMENT[];
+extern const char AE_CHECKED[];
+extern const char AE_UNCHECKED[];
+
+QT_END_NAMESPACE
+
+#endif // UISTRINGS_P_H