public boolean isPersistent() {
    return isPersistent;
  }
Removes any key-value pairs from @commonValuesMap that do not agree with the respective
key-value pairs of @additionalValuesMap

@param commonValuesMap Common values map, whose key set will be reduced.
@param additionalValuesMap Incoming values map, against which @commonValuesMap.
geode-gfsh/src/main/java/org/apache/geode/management/internal/cli/domain/RegionDescription.java