Represents a <flowRegíon> element.
Inheritance: SvgDrawableContainerBaseElement
        //==========================================================================
        public SvgFlowRootElement(SvgDocument document, SvgBaseElement parent, XElement flowRootElement)
            : base(document, parent, flowRootElement)
        {
            for(int i = 0; i < Children.Count; ++i)
              {
            FlowRegion = Children[i] as SvgFlowRegionElement;
            if(FlowRegion != null)
            {
              Children.RemoveAt(i);
              break;
            }
              }

              if(FlowRegion == null)
            throw new NotImplementedException();
        }
        //==========================================================================
        public SvgFlowRootElement(SvgDocument document, SvgBaseElement parent, XElement flowRootElement)
            : base(document, parent, flowRootElement)
        {
            for (int i = 0; i < Children.Count; ++i)
            {
                FlowRegion = Children[i] as SvgFlowRegionElement;
                if (FlowRegion != null)
                {
                    Children.RemoveAt(i);
                    break;
                }
            }

            if (FlowRegion == null)
            {
                throw new NotImplementedException();
            }
        }