[JavaScript][jQuery] chrome と safari を区別する

(function(jQuery){
	var userAgent = navigator.userAgent.toLowerCase();
	jQuery.browser = jQuery.extend(
		jQuery.browser
		,{
			version: ((!/chrome/.test( userAgent ) ? userAgent.match( /.+(?:rv|it|ra|ie)[\/: ]([\d.]+)/ ) : userAgent.match( /.+chrome\/([\d.]+)/ ) ) || [])[1] ,
			safari: /webkit/.test( userAgent ) && !/chrome/.test( userAgent ),
			chrome: /chrome/.test( userAgent )
		}
	);

	if (jQuery.browser.chrome) {
		jQuery.fn.extend({
			ready: function(fn) {
				// Attach the listeners
				bindReady();

				// If the DOM is already ready
				if ( jQuery.isReady )
					// Execute the function immediately
					fn.call( document, jQuery );

				// Otherwise, remember the function for later
				else
					// Add the function to the wait list
					jQuery.readyList.push( function() { return fn.call(this, jQuery); } );

				return this;
			}
		});

		var readyBound = false;
		function bindReady(){
			if ( readyBound ) return;
			readyBound = true;

			var numStyles;
			(function(){
				if (jQuery.isReady) return;
				if ( document.readyState != "loaded" && document.readyState != "complete" ) {
					setTimeout( arguments.callee, 0 );
					return;
				}
				if ( numStyles === undefined )
					numStyles = jQuery("style, link[rel=stylesheet]").length;
				if ( document.styleSheets.length != numStyles ) {
					setTimeout( arguments.callee, 0 );
					return;
				}
				// and execute any waiting functions
				jQuery.ready();
			})();

			// A fallback to window.onload, that will always work
			jQuery.event.add( window, "load", jQuery.ready );
		}
	}
})(jQuery);