form.field.Select: afterSetRecord() => removing old values from selections

old code:

    afterSetRecord(value, oldValue) {
        let me             = this,
            list           = me.list,
            selectionModel = list?.selectionModel,
            valueField     = me.valueField,
            nodeId;

        if (oldValue) {
            nodeId = list?.getItemId(oldValue[valueField]);

            selectionModel?.deselect(nodeId);
        }

        if (value) {
            nodeId = list?.getItemId(value[valueField]);

            selectionModel?.select(nodeId);
        }
    }

new code:

    afterSetRecord(value, oldValue) {
        if (this._picker?.isVisible) {
            let me             = this,
                selectionModel = me.list?.selectionModel;

            if (value) {
                selectionModel?.select(value);
            }
            else {
                selectionModel.deselectAll();
            }
        }
    }

we need a merge of both. if we are switching from one record to another, the old selection should get removed (i would not assume that the selModel has singleSelection activated).

if there is no value, we need the deselectAll() call.

@ExtAnimal