Editing A AS3 swf not popped error

Question

I'm editing a SWF but don't get the AS3 code. I'm trying to get: public function _-1XL(_arg1:BitmapData):void { this._-61F._-3zH(PNGEncoder.encode(_arg1)); }

But when I try to do it i get:

 public function _-1XL(_arg1:BitmapData):void
    {
        this._-61F._-3zH();
        return;
        /*not popped
        PNGEncoder.encode(_arg1)
        */
    }

Whit this AS3 code:

trait method QName(PackageNamespace(""), "_-1XL")
   method
    refid "_-44y:CameraViewFinder/_-1XL"
    param QName(PackageNamespace("flash.display"), "BitmapData")
    returns QName(PackageNamespace(""), "void")
    body
     maxstack 1
     localcount 2
     initscopedepth 4
     maxscopedepth 5
     code
      debugfile           "k"
      debugline           376
      getlocal0
      pushscope

      debug               1, "k", 0, 376
      debugline           406
      debugline           2
      getlocal0
      getproperty         QName(PrivateNamespace("_-3IL", "_-44y:CameraPhotoLab#0"), "_-61F")
      callpropvoid        QName(PackageNamespace(""), "_-3zH"), 1
            getlex              QName(PackageNamespace("_-1s1"), "PNGEncoder")
      getlocal1
      callproperty        QName(PackageNamespace(""), "encode"), 1
      coerce              QName(PackageNamespace("flash.utils"), "ByteArray")
      returnvoid
     end ; code
    end ; body
   end ; method
  end ; trait

Does someone knows how this works and can explain maybe what i did wrong? That should be really awesome!