Enable posting a message from JS to Android webview.

android_webview/java/src/org/chromium/android_webview/MessageChannel.java

Index: android_webview/java/src/org/chromium/android_webview/MessageChannel.java
diff --git a/android_webview/java/src/org/chromium/android_webview/MessageChannel.java b/android_webview/java/src/org/chromium/android_webview/MessageChannel.java
index 92486244618ad8a7eb30c2f506152d0732e37fbb..d2957ce41ec4de7ca920044285b8bc0e6472ec2e 100644
--- a/android_webview/java/src/org/chromium/android_webview/MessageChannel.java
+++ b/android_webview/java/src/org/chromium/android_webview/MessageChannel.java
@@ -9,20 +9,20 @@ package org.chromium.android_webview;
  * http://www.whatwg.org/specs/web-apps/current-work/multipage/web-messaging.html#message-channels
  */
 public class MessageChannel {
-    // The message port IDs of port1 and port2.
-    private int mPort1;
-    private int mPort2;
+    // The message ports of MessageChannel.
+    private MessagePort mPort1;
+    private MessagePort mPort2;
 
-    public MessageChannel(int port1, int port2) {
+    public MessageChannel(MessagePort port1, MessagePort port2) {
         mPort1 = port1;
         mPort2 = port2;
     }
 
-    public int port1() {
+    public MessagePort port1() {
         return mPort1;
     }
 
-    public int port2() {
+    public MessagePort port2() {
         return mPort2;
     }
 }