code: public final int invoke(@NonNull final ChronosOperation<?> operation,
              final boolean broadcastResult) {
          logd("invoking untagged operation");
          final int id = ChronosService.getInstance().runAsync(operation, broadcastResult);
          mUntaggedRequests.add(id);
          return id;
      }
docs: Launches an operation in background thread.
  
  @param operation       an operation to be launched
  @param broadcastResult {@code true} if the result should be broadcasted, {@code false}
  otherwise
  @return a unique launch id
  @see #invoke(ChronosOperation, String, boolean)
  @see #cancel(int, boolean)