public void planSkipped(NormalizationPlan.PlanType type) {
    // TODO: this appears to be used only for testing.
    if (worker != null) {
      worker.planSkipped(type);
    }
  }
Call-back for the case where plan couldn't be executed due to constraint violation, such as
namespace quota.
@param type type of plan that was skipped.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/normalizer/RegionNormalizerManager.java