Merge #14801: qt: Use window() instead of obsolete topLevelWidget()

0b4a5786bb Use window() instead of obsolete topLevelWidget() (Hennadii Stepanov)

Pull request description:

  `QWidget::topLevelWidget()` is obsolete since at least Qt 4.8.

  Refs:
  - https://doc-snapshots.qt.io/4.8/qwidget-obsolete.html#topLevelWidget
  - https://doc.qt.io/qt-5.9/qwidget-obsolete.html#topLevelWidget

Tree-SHA512: 45a79a3f11acd24bbf335603e60cb46545f4c9ce9b16280117676797a611c4422525abd39ad6784a7bc459926e3f5120b49a170403ff60ba4788d679862e3ff0

src/qt/guiutil.cpp

@@ -339,7 +339,7 @@ bool checkPoint(const QPoint &p, const QWidget *w)
 {
     QWidget *atW = QApplication::widgetAt(w->mapToGlobal(p));
     if (!atW) return false;
-    return atW->topLevelWidget() == w;
+    return atW->window() == w;
 }
 
 bool isObscured(QWidget *w)