[QM] Editor is broken once Copy Formatting is added

[Marek Lewandowski]

The problem is caused by ​this line. Simply there's no underlying querySelectorAll method in QM.

It can be avoided by simply changing function to the following:

_getScreenReaderContainer: function() {
	if ( CKEDITOR.env.ie6Compat ) {
		// findOne is not supported on Quirks.
		return null;
	}

	return CKEDITOR.document.getBody().findOne( '.cke_copyformatting_notification div[aria-live]' );
}