Scatter plot does not detect coloring changes

[janezd]

Describe the bug

Scatter plot ignores data input when the affected attributes are unchanged. Other projections probably have a similar problem and it probably also affects size and shape.

To Reproduce

1. Connect File -> Color -> Scatter plot
2. In Scatter plot, set color to Cholesterol. X and Y should be, say, age and rest SBP.
3. In Color, change the color for max HR.
4. In Scatter plot, set color to max HR.

After this, max HR will be shown in the original color. I suspect that this occurs because at step 3 "max HR" was not in effective_data, so scatter plot ignored the new data input.

Expected behavior

I suppose projections should be more careful with effective_data. Perhaps this mechanism is flawed.