Enable posting a message from JS to Android webview.

android_webview/browser/aw_message_port_service.h

Index: android_webview/browser/aw_message_port_service.h
diff --git a/android_webview/browser/aw_message_port_service.h b/android_webview/browser/aw_message_port_service.h
new file mode 100644
index 0000000000000000000000000000000000000000..086480e75d77951b649f9ab7196cdff2bfea15a7
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+++ b/android_webview/browser/aw_message_port_service.h
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+// 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_