Enable posting a message from JS to Android webview.

android_webview/java/src/org/chromium/android_webview/AwBrowserContext.java

 // Copyright 2013 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.android_webview;
 
 import android.content.Context;
 import android.content.SharedPreferences;
 
 import org.chromium.content.browser.ContentViewStatics;
@@ skipping 10 matching lines @@
 
     private static final String HTTP_AUTH_DATABASE_FILE = "http_auth.db";
 
     private SharedPreferences mSharedPreferences;
 
     private AwGeolocationPermissions mGeolocationPermissions;
     private AwCookieManager mCookieManager;
     private AwFormDatabase mFormDatabase;
     private HttpAuthDatabase mHttpAuthDatabase;
     private DefaultAndroidKeyStore mLocalKeyStore;
+    private AwMessagePortService mMessagePortService;
 
     public AwBrowserContext(SharedPreferences sharedPreferences) {
         mSharedPreferences = sharedPreferences;
     }
 
     public AwGeolocationPermissions getGeolocationPermissions() {
         if (mGeolocationPermissions == null) {
             mGeolocationPermissions = new AwGeolocationPermissions(mSharedPreferences);
         }
         return mGeolocationPermissions;
@@ skipping 20 matching lines @@
         return mHttpAuthDatabase;
     }
 
     public DefaultAndroidKeyStore getKeyStore() {
         if (mLocalKeyStore == null) {
             mLocalKeyStore = new DefaultAndroidKeyStore();
         }
         return mLocalKeyStore;
     }
 
+    public AwMessagePortService createMessagePortService() {
+        if (mMessagePortService == null) {
+            mMessagePortService = new AwMessagePortService();
+        }
+        return mMessagePortService;
+    }
+
     /**
      * @see android.webkit.WebView#pauseTimers()
      */
     public void pauseTimers() {
         ContentViewStatics.setWebKitSharedTimersSuspended(true);
     }
 
     /**
      * @see android.webkit.WebView#resumeTimers()
      */
     public void resumeTimers() {
         ContentViewStatics.setWebKitSharedTimersSuspended(false);
     }
 }