[Issue] Line chart and area chart on same axes

Hello,
If more series are in the same axis, the series of type area must be the first of the axis, otherwise, the chart shows a line chart.

Steps to Reproduce

  1. Define a new chart.
  2. Add a series (A) and set the chart type to line
  3. Add the second series (B) and set the chart type to area

As you should see, the B is a line chart and not an area chart.
If you move the B series before the A series, B became an area chart.

Thank you,
Domenico

Could you put that together in a codepen/jsfiddle/jsbin? define and add can mean many things.