Enable posting a message from JS to Android webview.

android_webview/browser/aw_message_port_service.h

+// Copyright 2015 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.
+
+#ifndef ANDROID_WEBVIEW_BROWSER_AW_MESSAGE_PORT_SERVICE_H_
+#define ANDROID_WEBVIEW_BROWSER_AW_MESSAGE_PORT_SERVICE_H_
+
+#include <vector>
+
+#include "base/values.h"
+
+namespace android_webview {
+
+class AwMessagePortMessageFilter;
+
+// The interface for AwMessagePortService
+class AwMessagePortService  {
+ public:
+  virtual ~AwMessagePortService() { }
+
+  virtual void OnConvertedMessage(
+      int message_port_id,
+      const base::ListValue& message,
+      const std::vector<int>& sent_message_port_ids) = 0;
+
+  virtual void OnMessagePortMessageFilterClosing(
+      AwMessagePortMessageFilter* filter) = 0;
+};
+
+}  // namespace android_webview
+
+#endif  // ANDROID_WEBVIEW_BROWSER_AW_MESSAGE_PORT_SERVICE_H_