Client: Workaround for QPlatformWindow::setVisible(true) being called twice

Fixes a crash.

Otherwise we created two shell surface objects in some cases.

Change-Id: Ieded56261061da6acf27ccabba81c8f578ca1596
Reviewed-by: Pier Luigi Fiorini <pierluigi.fiorini@liri.io>

src/plugins/platforms/wayland/qwaylandwindow.cpp

@@ -414,6 +414,11 @@ QPlatformScreen *QWaylandWindow::calculateScreenFromSurfaceEvents() const
 
 void QWaylandWindow::setVisible(bool visible)
 {
+    // Workaround for issue where setVisible may be called with the same value twice
+    if (lastVisible == visible)
+        return;
+    lastVisible = visible;
+
     if (visible) {
         if (window()->type() == Qt::Popup || window()->type() == Qt::ToolTip)
             activePopups << this;

src/plugins/platforms/wayland/qwaylandwindow_p.h

@@ -270,6 +270,7 @@ private:
     void handleScreensChanged();
 
     bool mInResizeFromApplyConfigure = false;
+    bool lastVisible = false;
     QRect mLastExposeGeometry;
 
     static const wl_callback_listener callbackListener;