Fix build with -no-feature-action

/home/tasuku/io/qt/code/qt/qt5/qtlite/qt5/qtbase/src/plugins/platformthemes/gtk3/qgtk3interface.cpp:640:59: error: return type ‘class QIcon’ is incomplete
  640 | QIcon QGtk3Interface::fileIcon(const QFileInfo &fileInfo) const

Pick-to: 6.5
Change-Id: I2936a3d7ae4cca200f946103b97659819775a8da
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

src/plugins/platformthemes/gtk3/qgtk3interface_p.h

@@ -19,6 +19,7 @@
 #include <QtCore/QCache>
 #include <private/qflatmap_p.h>
 #include <QtCore/QObject>
+#include <QtGui/QIcon>
 #include <QtGui/QPalette>
 #include <QtWidgets/QWidget>
 #include <QtCore/QLoggingCategory>

src/widgets/kernel/qwidget.h

@@ -8,7 +8,9 @@
 #include <QtGui/qwindowdefs.h>
 #include <QtCore/qobject.h>
 #include <QtCore/qmargins.h>
+#if QT_CONFIG(action)
 #include <QtGui/qaction.h>
+#endif
 #include <QtGui/qpaintdevice.h>
 #include <QtGui/qpalette.h>
 #include <QtGui/qfont.h>
@@ -175,6 +177,7 @@ class Q_WIDGETS_EXPORT QWidget : public QObject, public QPaintDevice
     Q_PROPERTY(QString windowFilePath READ windowFilePath WRITE setWindowFilePath)
     Q_PROPERTY(Qt::InputMethodHints inputMethodHints READ inputMethodHints WRITE setInputMethodHints)
 
+#if QT_CONFIG(action)
 #if 0
     // ### TODO: make this work (requires SFINAE-friendly connect())
     template <typename...Args>
@@ -197,6 +200,8 @@ class Q_WIDGETS_EXPORT QWidget : public QObject, public QPaintDevice
             std::negation<std::is_convertible<Args, QString>>...
         >>;
 #endif
+#endif // QT_CONFIG(action)
+
 public:
     enum RenderFlag {
         DrawWindowBackground = 0x1,