Provide a mechanism for the GCM driver to send message receipts to GCM.

components/gcm_driver/gcm_driver_android.cc

Index: components/gcm_driver/gcm_driver_android.cc
diff --git a/components/gcm_driver/gcm_driver_android.cc b/components/gcm_driver/gcm_driver_android.cc
index a512e8248d9a045c091c9c2440ec80577d1b26d8..4aaf9ca003d21d2edcd41c685753ef64db492f02 100644
--- a/components/gcm_driver/gcm_driver_android.cc
+++ b/components/gcm_driver/gcm_driver_android.cc
@@ -109,7 +109,13 @@ void GCMDriverAndroid::OnMessageReceived(
   recorder_.RecordDataMessageReceived(app_id, message.sender_id,
                                       message_byte_size);
 
-  DispatchMessage(app_id, message);
+  DispatchMessage(app_id, message,
+                  base::Bind(&GCMDriverAndroid::SendMessageReceipt,
+                             weak_ptr_factory_.GetWeakPtr()));
+}
+
+void GCMDriverAndroid::SendMessageReceipt(GCMMessageStatus status) {
+  // TODO(harkness) Implement message receipts in android. crbug.com/674131.
 }
 
 // static