Close popups on WASM window non-client area interactions

This mimics the behavior displayed by the Cocoa window

Fixes: QTBUG-111436
Change-Id: I800fd15e870e54cf2c22ba5bd7f0c8b3f7f85bbf
Reviewed-by: Piotr Wierciński <piotr.wiercinski@qt.io>
Reviewed-by: Lorn Potter <lorn.potter@gmail.com>

src/plugins/platforms/wasm/qwasmwindow.cpp

@@ -162,6 +162,7 @@ void QWasmWindow::onNonClientAreaInteraction()
 {
     if (!isActive())
         requestActivateWindow();
+    QGuiApplicationPrivate::instance()->closeAllPopups();
 }
 
 bool QWasmWindow::onNonClientEvent(const PointerEvent &event)