[Lens] Remember last-used configuration when switching between incompatible configurations

[wylieconlon]

In general, users are expecting the Lens editor to have a "memory" when switching from one configuration to another, and then back. This is particular important when they are temporarily looking at something that is incompatible, such as:

• Switching between incompatible functions, such as Date Histogram -> Terms -> Date Histogram. In this case the user would expect the field that they previously selected to still be selected
• Switching between the XY chart and pie charts, the user is reset to the default visualization options each time. Users would expect any visualization-specific settings to be kept

cc @AlonaNadler if you can come up with other examples

Implementation note

I think these features should be implemented separately. I don't think they can or should be implemented as a general undo/redo system, because it's specific to certain flows.

• When switching incompatible functions, the datasource could track "previous functions" for the specific dimension, and restore on switch. This state should not be saved in the Lens doc.
• When switching between completely separate chart types, the editor frame would need to be involved to store a "previous state" and restore it by applying equality checks, for example equality of the column IDs and metadata. This should not be saved in the Lens doc.

[elasticmachine]

Pinging @elastic/kibana-app (Team:KibanaApp)

[stratoula]

This seems related to the undo redo functionality

[stratoula]

Closing this as this will be solved when we have the undo redo functionality #54971