only switch to swf fallback on known mediaerrors
only switch to swf fallback on known mediaerrors

ilovezy/webshim,fashionsun/webshim,tomascassidy/webshim,webdev1001/webshim,fashionsun/webshim,aFarkas/webshim,webdev1001/webshim,aFarkas/webshim,fashionsun/webshim,tomascassidy/webshim,pablogrela/webshim,cl4rke/webshim,aFarkas/webshim,tomascassidy/webshim,cl4rke/webshim,ilovezy/webshim,pablogrela/webshim,pablogrela/webshim,ilovezy/webshim,cl4rke/webshim,webdev1001/webshim