Make the fuchsia mojo/public repo the source of truth.

mojo/public/java/system/src/org/chromium/mojo/system/AsyncWaiter.java

-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-package org.chromium.mojo.system;
-
-import org.chromium.mojo.system.Core.HandleSignals;
-
-/**
- * A class which implements the {@link AsyncWaiter} allows asynchronously waiting on a background
- * thread.
- */
-public interface AsyncWaiter {
-
-    /**
-     * Allows cancellation of an asyncWait operation.
-     */
-    interface Cancellable {
-        /**
-         * Cancels an asyncWait operation. Has no effect if the operation has already been canceled
-         * or the callback has already been called.
-         * <p>
-         * Must be called from the same thread as {@link AsyncWaiter#asyncWait} was called from.
-         */
-        void cancel();
-    }
-
-    /**
-     * Callback passed to {@link AsyncWaiter#asyncWait}.
-     */
-    public interface Callback {
-        /**
-         * Called when the handle is ready.
-         */
-        public void onResult(int result);
-
-        /**
-         * Called when an error occurred while waiting.
-         */
-        public void onError(MojoException exception);
-    }
-
-    /**
-     * Asynchronously call wait on a background thread. The given {@link Callback} will be notified
-     * of the result of the wait on the same thread as asyncWait was called.
-     *
-     * @return a {@link Cancellable} object that can be used to cancel waiting. The cancellable
-     *         should only be used on the current thread, and becomes invalid once the callback has
-     *         been notified.
-     */
-    Cancellable asyncWait(Handle handle, HandleSignals signals, long deadline, Callback callback);
-
-}