combiner = null;
    // combiner should be collected even if the future it returns never completes.
    GcFinalization.awaitClear(combinerRef);
  }

  /*
   * TODO(cpovirk): maybe pass around TestFuture instances instead of
   * ListenableFuture instances
   */

  /**
   * A future in {@link TestFutureBatch} that also has a name for debugging purposes and a {@code

    combiner = null;
    // combiner should be collected even if the future it returns never completes.
    GcFinalization.awaitClear(combinerRef);
  }

  /*
   * TODO(cpovirk): maybe pass around TestFuture instances instead of
   * ListenableFuture instances
   */

  /**
   * A future in {@link TestFutureBatch} that also has a name for debugging purposes and a {@code

     * building for Android): Ensure that any object you pass implements the interface not just in
     * your current SDK version but also at the oldest version you support. For example, <a
     * href="https://developer.android.com/sdk/api_diff/16/">API Level 16</a> is the first version
     * in which {@code Cursor} is {@code Closeable}. To support older versions, pass a wrapper

     * building for Android): Ensure that any object you pass implements the interface not just in
     * your current SDK version but also at the oldest version you support. For example, <a
     * href="https://developer.android.com/sdk/api_diff/16/">API Level 16</a> is the first version
     * in which {@code Cursor} is {@code Closeable}. To support older versions, pass a wrapper