code: int getIndirectCE32(int ce32) {
          assert(Collation.isSpecialCE32(ce32));
          int tag = Collation.tagFromCE32(ce32);
          if(tag == Collation.DIGIT_TAG) {
              // Fetch the non-numeric-collation CE32.
              ce32 = ce32s[Collation.indexFromCE32(ce32)];
          } else if(tag == Collation.LEAD_SURROGATE_TAG) {
              ce32 = Collation.UNASSIGNED_CE32;
          } else if(tag == Collation.U0000_TAG) {
              // Fetch the normal ce32 for U+0000.
              ce32 = ce32s[0];
          }
          return ce32;
      }
docs: Returns the CE32 for an indirect special CE32 (e.g., with DIGIT_TAG).
  Requires that ce32 is special.