Removing items from chart at runtime causes RTE in addition to not removing the canvas

Steps to reproduce:
1. Select a drawing from the combo. say ellipse and rect.
2. Then click "remove items" till the particular month from where the drawing is rendered is removed.

Actual Results: RTE is thrown and application does not respond after this. Column chart the canvas is removed, but the particular item in the chart is not. In bar chart the canvas is not removed, but the item(example Jan) is removed

Expected Results: No RTE and the canvas and items should be removed from the chart