Add AsyncWaiter implementation to java API.

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

Index: mojo/public/java/src/org/chromium/mojo/system/AsyncWaiterCallback.java
diff --git a/mojo/public/java/src/org/chromium/mojo/system/AsyncWaiterCallback.java b/mojo/public/java/src/org/chromium/mojo/system/AsyncWaiterCallback.java
new file mode 100644
index 0000000000000000000000000000000000000000..4217bbfe4f12a2c50f5f0b409b34cde9f2480476
--- /dev/null
+++ b/mojo/public/java/src/org/chromium/mojo/system/AsyncWaiterCallback.java
@@ -0,0 +1,20 @@
+// 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;
+
+/**
+ * Callback passed to {@link AsyncWaiter#asyncWait}.
+ */
+public interface AsyncWaiterCallback {

[bulach, 2014/05/15 19:32:58]

nit: if this can only be used within the AsyncWaiter context, then having it as
inner interface there (like Cancellable) would keep it more contained.

[rmcilroy, 2014/05/15 22:36:51]

+1

[qsr, 2014/05/19 12:12:09]

 That was causing an issue with our jni generator. Updated the generator in a //
CL, and move this class to  AsyncWaiter

+    /**
+     * Called when the handle is ready.
+     */
+    public void onResult(int result);
+
+    /**
+     * Called when an error occurred while waiting.
+     */
+    public void onError(MojoException exception);
+}