anchor.diff:    // Track overlays for z-index and focus managemant.
     static List overlays = [];
   
  -  static void trackOverlays(inOverlay) {
  +  static void _trackOverlays(inOverlay) {
       if (inOverlay.opened) {
  -      var z0 = currentOverlayZ();
  +      var z0 = _currentOverlayZ();
         overlays.add(inOverlay);
  -      var z1 = currentOverlayZ();
  +      var z1 = _currentOverlayZ();
         if (z0 != null && z1 != null && z1 <= z0) {
  -        applyOverlayZ(inOverlay, z0);
  +        _applyOverlayZ(inOverlay, z0);
         }
       } else {
         var i = overlays.indexOf(inOverlay);
         if (i >= 0) {
           overlays.removeAt(i);
  -        setZ(inOverlay, null);
  +        _setZ(inOverlay, null);
         }
       }
     }
   
  -  static void applyOverlayZ(inOverlay, inAboveZ) {
  -    setZ(inOverlay, inAboveZ + 2);
  -  }
  -
  -  static void setZ(inNode, inZ) {
  +  static void _applyOverlayZ(inOverlay, inAboveZ) {
  +    _setZ(inOverlay, inAboveZ + 2);
  +  }
  +
  +  static void _setZ(inNode, inZ) {
       inNode.style.zIndex = "$inZ";
     }
   
  -  static currentOverlay() {
  +  static _currentOverlay() {
       return overlays.isNotEmpty ? overlays.last : null;
     }
   
  -  static int DEFAULT_Z = 1000;
  -
  -  static currentOverlayZ() {
  -    var z = DEFAULT_Z;
  -    var current = currentOverlay();
  +  // TODO(ussuri): This widget doesn't know in which z-index environment it's
  +  // going to live. Choosing an arbitrary starting z-index here is wrong. Redo.
  +  static int _DEFAULT_Z = 1000;
  +
  +  static _currentOverlayZ() {
  +    var z = _DEFAULT_Z;
  +    var current = _currentOverlay();
       if (current != null) {
  -      var z1 = current.getComputedStyle().zIndex;
  +      final z1 = current.getComputedStyle().zIndex;
         z = int.parse(z1, onError: (source) { });
       }
       return z;
     }
   
  -  static void focusOverlay() {
  -    var current = currentOverlay();
  +  static void _focusOverlay() {
  +    var current = _currentOverlay();
       if (current != null) {
         current.focus();
       }
  
positive.code:    * method to adjust the size and position of the overlay when the
     * browser window resizes.
     */
    void resizeHandler(e) {
    }
  }
  
negative.code:         e..stopPropagation()..preventDefault();
        }
        if (autoClose) {
          _autoCloseTask = new Timer(Duration.ZERO, () { opened = false; });
        }
      }
    }
  
    bool _isPointInOverlay(Point xyGlobal) {
      return super.getBoundingClientRect().containsPoint(xyGlobal);
    }
  
    void _keyDownHandler(KeyboardEvent e) {
      if (e.keyCode == KeyCode.ESC) {
        opened = false;
      }
  