[GCM] Adding the OnSendAcknowledgement event

components/invalidation/gcm_invalidation_bridge.cc

 // Copyright 2014 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.
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/single_thread_task_runner.h"
 #include "base/thread_task_runner_handle.h"
 #include "components/gcm_driver/gcm_driver.h"
 #include "components/invalidation/gcm_invalidation_bridge.h"
@@ skipping 314 matching lines @@
   // callback so this should be no-op in desktop version as well.
 }
 
 void GCMInvalidationBridge::OnSendError(
     const std::string& app_id,
     const gcm::GCMClient::SendErrorDetails& send_error_details) {
   // cacheinvalidation doesn't send messages over GCM.
   NOTREACHED();
 }
 
+void GCMInvalidationBridge::OnSendAcknowledged(
+    const std::string& app_id,
+    const std::string& message_id) {
+  // cacheinvalidation doesn't send messages over GCM.
+  NOTREACHED();
+}
+
 void GCMInvalidationBridge::OnConnected(const net::IPEndPoint& ip_endpoint) {
   core_thread_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(
           &GCMInvalidationBridge::Core::OnConnectionStateChanged, core_, true));
 }
 
 void GCMInvalidationBridge::OnDisconnected() {
   core_thread_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&GCMInvalidationBridge::Core::OnConnectionStateChanged,
                  core_,
                  false));
 }
 
 
 }  // namespace invalidation