Add postMessage APIs to the support lib

customtabs/src/android/support/customtabs/CustomTabsClient.java

 /*
  * Copyright (C) 2015 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
@@ skipping 157 matching lines @@
     }
 
     /**
      * Creates a new session through an ICustomTabsService with the optional callback. This session
      * can be used to associate any related communication through the service with an intent and
      * then later with a Custom Tab. The client can then send later service calls or intents to
      * through same session-intent-Custom Tab association.
      * @param callback The callback through which the client will receive updates about the created
      *                 session. Can be null.
      * @return The session object that was created as a result of the transaction. The client can
-     *         use this to relay {@link CustomTabsSession#mayLaunchUrl(Uri, Bundle, List)} calls.
+     *         use this to relay session specific calls.
      *         Null on error.
      */
     public CustomTabsSession newSession(final CustomTabsCallback callback) {
         ICustomTabsCallback.Stub wrapper = new ICustomTabsCallback.Stub() {

[Benoit L, 2016/11/07 17:50:38]

What about a proxy class:

    /** Posts the callback to the main thread. */
    private static class CustomTabsCallbackProxy extends
ICustomTabsCallback.Stub {
        private final Handler mHandler;
        private final CustomTabsCallback mCallback;

        public CustomTabsCallbackProxy(CustomTabsCallback callback) {
            mHandler = new Handler(Looper.getMainLooper());
            mCallback = callback;
        }

        @Override
        public void onNavigationEvent(final int navigationEvent, final Bundle
extras) {
            if (mCallback == null) return;
            mHandler.post(new Runnable() {
                @Override
                public void run() {
                    mCallback.onNavigationEvent(navigationEvent, extras);
                }
            });
        }

        @Override
        public void extraCallback(final String callbackName, final Bundle args)
                throws RemoteException {
            if (callback == null) return;
            mHandler.post(new Runnable() {
                @Override
                public void run() {
                    mCallback.extraCallback(callbackName, args);
                }
            });
        }
    }


And then, here:
        CustomTabsCallbackProxy proxy = new CustomTabsCallbackProxy(callback);

[Yusuf, 2016/11/07 18:56:41]

Done.

             @Override
             public void onNavigationEvent(int navigationEvent, Bundle extras) {
                 if (callback != null) callback.onNavigationEvent(navigationEvent, extras);
             }
 
             @Override
+            public void onMessageChannelReady(Uri origin, Bundle extras) {
+                if (callback != null) callback.onMessageChannelReady(origin, extras);
+            }
+
+            @Override
+            public void onPostMessage(String message, Bundle extras) {
+                if (callback != null) callback.onPostMessage(message, extras);
+            }
+
+            @Override
             public void extraCallback(String callbackName, Bundle args) throws RemoteException {
                 if (callback != null) callback.extraCallback(callbackName, args);
             }
         };
 
         try {
             if (!mService.newSession(wrapper)) return null;
         } catch (RemoteException e) {
             return null;
         }
         return new CustomTabsSession(mService, wrapper, mServiceComponentName);
     }
 
     public Bundle extraCommand(String commandName, Bundle args) {
         try {
             return mService.extraCommand(commandName, args);
         } catch (RemoteException e) {
             return null;
         }
     }
 }