QmlDesigner: Define RegExpValidator in HelperWidgets

In Qt 6 there is no RegExpValidator anymore.
To support both Qt 5 and Qt 6 we register our own RegExpValidator
in HelperWidgets if we compile with Qt 6.

Change-Id: I7e66cbf3e29dd034a1c96a22e233058cb7a892e3
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@qt.io>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

share/qtcreator/qmldesigner/propertyEditorQmlSources/RegExpValidator.qml

@@ -0,0 +1,6 @@
+import QtQuick 2.15
+
+RegularExpressionValidator {
+    id: root
+    property alias regExp: root.regularExpression
+}

src/plugins/qmldesigner/components/propertyeditor/quick2propertyeditorview.cpp

@@ -25,22 +25,23 @@
 
 #include "quick2propertyeditorview.h"
 
-#include "propertyeditorvalue.h"
+#include "aligndistribute.h"
+#include "annotationeditor/annotationeditor.h"
+#include "bindingeditor/actioneditor.h"
+#include "bindingeditor/bindingeditor.h"
 #include "fileresourcesmodel.h"
 #include "gradientmodel.h"
-#include "gradientpresetdefaultlistmodel.h"
 #include "gradientpresetcustomlistmodel.h"
+#include "gradientpresetdefaultlistmodel.h"
 #include "itemfiltermodel.h"
-#include "simplecolorpalettemodel.h"
-#include "bindingeditor/bindingeditor.h"
-#include "bindingeditor/actioneditor.h"
-#include "annotationeditor/annotationeditor.h"
-#include "qmlanchorbindingproxy.h"
-#include "theme.h"
-#include "aligndistribute.h"
 #include "propertyeditorcontextobject.h"
-#include "tooltip.h"
+#include "propertyeditorqmlbackend.h"
+#include "propertyeditorvalue.h"
+#include "qmlanchorbindingproxy.h"
 #include "richtexteditor/richtexteditorproxy.h"
+#include "simplecolorpalettemodel.h"
+#include "theme.h"
+#include "tooltip.h"
 
 namespace QmlDesigner {
 
@@ -71,6 +72,11 @@ void Quick2PropertyEditorView::registerQmlTypes()
         Tooltip::registerDeclarativeType();
         EasingCurveEditor::registerDeclarativeType();
         RichTextEditorProxy::registerDeclarativeType();
+        QUrl regExpUrl = QUrl::fromLocalFile(PropertyEditorQmlBackend::propertyEditorResourcesPath()
+                                             + "/RegExpValidator.qml");
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+        qmlRegisterType(regExpUrl, "HelperWidgets", 2, 0, "RegExpValidator");
+#endif
     }
 }