message: Fix build time error in OptimizeEnumsPass
  Summary:
  The abstract domain in the pass did not handle well enough for null values.
  This temporary fix may cause some regression.
diff: @@ -404,7 +404,7 @@ class EnumUpcastDetector {
  reject(insn, possible_type, rejected_enums, reason);
  }
  }
  - if (need_delete) {
  + if (need_delete || types.size() == 0) {
  reject(insn, required_type, rejected_enums, reason);
  }
  } else {
  