AxisMinimum issue with StackedArea Chart

It display DataPoint even YValue of the DataPoint is less than the AxisMinimum 
for StackedArea.

Example:- If AxisMinimum=20 and DataPoint's YValue=15 for any particular 
DataPoint, then this DataPoint will still display in chart.

Test Cases:-
<vc:Chart xmlns:vc="clr-namespace:Visifire.Charts;assembly=SLVisifire.Charts" 
                  Width="490" Height="290" Theme="Theme1" x:Name="chart" ZoomingEnabled="True" View3D="False">

            <vc:Chart.Titles>
                <vc:Title Text="Athens 2004 Olympics" DockInsidePlotArea="True"/>
            </vc:Chart.Titles>

            <vc:Chart.AxesX>
                <vc:Axis />
            </vc:Chart.AxesX>

            <vc:Chart.AxesY>
                <vc:Axis AxisMinimum="20" AxisType="Primary"/>
            </vc:Chart.AxesY>

            <vc:Chart.Series>

                <vc:DataSeries RenderAs="StackedArea" AxisYType="Primary" ShowInLegend="True" >
                    <vc:DataSeries.DataPoints>
                        <vc:DataPoint AxisXLabel="USA" YValue="50"/>
                        <vc:DataPoint AxisXLabel="China" YValue="35"/>
                        <vc:DataPoint AxisXLabel="Russia" YValue="45"/>
                        <vc:DataPoint AxisXLabel="Australia" YValue="4"/>
                        <vc:DataPoint AxisXLabel="Japan" YValue="12"/>
                    </vc:DataSeries.DataPoints>
                </vc:DataSeries>  

            </vc:Chart.Series>
        </vc:Chart>

Original issue reported on code.google.com by shoaibi...@gmail.com on 6 Jan 2011 at 10:11

zhangzy0193 / visifire

AxisMinimum issue with StackedArea Chart #313