anchor.diff:      if (_decoration.border == null)
         return;
   
  -    if (_hasUniformBorder) {
  +    if (_decoration.border.isUniform) {
         if (_decoration.borderRadius != null) {
           _paintBorderWithRadius(canvas, rect);
           return;
  
positive.code:   }
  
    void _paintBorderWithCircle(Canvas canvas, Rect rect) {
      assert(_hasUniformBorder);
      assert(_decoration.shape == BoxShape.circle);
      assert(_decoration.borderRadius == null);
      double width = _decoration.border.top.width;
  
negative.code:   bool operator ==(dynamic other) {
      if (identical(this, other))
        return true;
      if (other.runtimeType != runtimeType)
        return false;
      final Border typedOther = other;
      return top == typedOther.top &&
  