Prevent Iframe access error

I have this error when the script is embedded in iframe (ie. in a Facebook App or loaded from another subdomain) : 

Uncaught SecurityError: Blocked a frame with origin "http://xxxx" from accessing a frame with origin "http://localhost". Protocols, domains, and ports must match.  @line jquery.mb.YTPlayer.js:153

I put quickly this to fix it : 

try{
    var canGoFullscreen = !(jQuery.browser.msie || jQuery.browser.opera || self.location.href != top.location.href);
} catch(Exception){
    var canGoFullscreen = false;
}

So now the script works even if loaded from an iframe or another domain or in a Facebook apps. I don't know what will be your strategy for this (if you want also to check jQuery.browser.msie or if we have access to the top.location.href) => so I propose the safer way with a try method and if any error => canGoFullscreen = false.