message: Do not delete column key in matrix row with non undefined editingObj
diff: @@ -2292,6 +2292,7 @@ export class QuestionMatrixDropdownModelBase
  var newValue = this.createNewValue();
  for (var i = 0; i < rows.length; i++) {
  var row = rows[i];
  + if (!!row.editingObj) continue;
  var rowValue = this.getRowValue(i);
  var rValue = row.value;
  if (this.isTwoValueEquals(rowValue, rValue)) continue;
  @@ -2778,6 +2779,7 @@ export class QuestionMatrixDropdownModelBase
  isDeletingValue: boolean,
  newValue: any
  ): any {
  + if (!!row.editingObj) return;
  var rowValue = this.getRowValueCore(row, newValue, true);
  if (isDeletingValue) {
  delete rowValue[columnName];
  