Create a chart. For this test, I used two columns with values 1-10 in them, but
it appears the actual data source values are not important here.

1. Create the chart - I used default values throughout.
2. Resize the chart so you can see what you're doing
3. Double click on the chart to enter chart edit mode.
4. Note that by default the legend box appears to the right of the chart.
5. Click in the legend box (or the title box, or the chart itself, or the axis
label boxes) to select it.
6. Drag it someone else
7. Press ctrl-z and watch it either jump back to the default position (not
necessarily the position it came from), or do nothing at all.

Note - The undo function does appear to work as expected if you relocate the
legend/title/axis/etc by going into its properties, Position, then selecting one
of left/top/bottom/right, but inconsistant thing result when I move the object
by dragging with the mouse.