Pop pages that were opened during editing after editing

If a face configuration page was opened during editing and not closed when exiting editing, it will break when we switch back to pageContents with the effect that changed face settings are not applied anymore until the app is restarted. This manifests in error messages such as FaceConfigurationPage.qml:189: TypeError: Cannot read property 'controller' of null When we properly pop the page of the stack it works as expected.