* could in principle cause problems for some users. Still, we expect that the benefits of the
 * nullness annotations in particular will outweigh the costs. (And it's worth noting that we have
 * released multiple ListenableFuture.class files that are not byte-for-byte compatible even from
 * the beginning, thanks to using different `-source -target` values for compiling our `-jre` and

      void onInvoke(Object error);
    }

    void onInvoke(ResolveCallbackFn<T> resolve, RejectCallbackFn reject);
  }

  public Promise(PromiseExecutorCallbackFn<T> executor) {}

  @Override
  public native <V extends @Nullable Object> Promise<V> then(
      @JsOptional @Nullable IThenOnFulfilledCallbackFn<? super T, ? extends V> onFulfilled,
      @JsOptional @Nullable IThenOnRejectedCallbackFn<? extends V> onRejected);

 * could in principle cause problems for some users. Still, we expect that the benefits of the
 * nullness annotations in particular will outweigh the costs. (And it's worth noting that we have
 * released multiple ListenableFuture.class files that are not byte-for-byte compatible even from
 * the beginning, thanks to using different `-source -target` values for compiling our `-jre` and