code: public List<Symbol> getAllSymbolsForType(JSType type) {
      if (type == null) {
        return ImmutableList.of();
      }
  
      UnionType unionType = type.toMaybeUnionType();
      if (unionType != null) {
        List<Symbol> result = new ArrayList<>(2);
        for (JSType alt : unionType.getAlternates()) {
          // Our type system never has nested unions.
          Symbol altSym = getSymbolForTypeHelper(alt, true);
          if (altSym != null) {
            result.add(altSym);
          }
        }
        return result;
      }
      Symbol result = getSymbolForTypeHelper(type, true);
      return result == null ? ImmutableList.of() : ImmutableList.of(result);
    }
docs: Gets all symbols associated with the given type. For union types, this may be multiple symbols.
  For instance types, this will return the constructor of that instance.