Why use beginBitmapFill when you have the Bitmap class for this? Just use :

Code:
var image:Test = new Test();
var bmp:Bitmap=new Bitmap();
bmp.bitmapData=image;
this.addChild(bmp);
or, a bit shorter :

Code:
var bmp:Bitmap=new Bitmap();
bmp.bitmapData=new Test();
this.addChild(bmp);