*   triggered handleException.)
       *
       * TODO(cpovirk): Think about whether we could/should use Verify to check the return value of
       * addCausalChain.
       */
      boolean unused = addCausalChain(seen, requireNonNull(tryInternalFastPathGetFailure()));
    }
  }

  /**
   * Collects the result (success or failure) of one input future. The input must not have been