Fix android menubar's menu not opening at the first press.

In case of selected item in submenu, call aboutToHide() on still
visible menus. This will allow quickquickcontrols to act
poperly when menus are closed.

Task-number: QTBUG-42188
Change-Id: I9f11fa7cc63f50d7863566d0ee52a62c7036ddaa
Reviewed-by: Alex Blasche <alexander.blasche@theqtcompany.com>

src/plugins/platforms/android/androidjnimenu.cpp

@@ -350,6 +350,10 @@ namespace QtAndroidMenu
                 item->activated();
                 visibleMenu->aboutToHide();
                 visibleMenu = 0;
+                foreach (QAndroidPlatformMenu *menu, pendingContextMenus) {
+                    if (menu->isVisible())
+                        menu->aboutToHide();
+                }
                 pendingContextMenus.clear();
             }
         }