[GCM] Exposing persistence of account mappings in GCM Driver

components/gcm_driver/gcm_driver_android.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 "components/gcm_driver/gcm_driver_android.h"
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_array.h"
 #include "base/android/jni_string.h"
 #include "base/compiler_specific.h"
@@ skipping 111 matching lines @@
     const GetGCMStatisticsCallback& callback,
     bool clear_logs) {
   NOTIMPLEMENTED();
 }
 
 void GCMDriverAndroid::SetGCMRecording(const GetGCMStatisticsCallback& callback,
                                        bool recording) {
   NOTIMPLEMENTED();
 }
 
+void GCMDriverAndroid::UpdateAccountMapping(
+    const AccountMapping& account_mapping) {
+}
+
+void GCMDriverAndroid::RemoveAccountMapping(const std::string& account_id) {
+}
+
 GCMClient::Result GCMDriverAndroid::EnsureStarted() {
   // TODO(johnme): Maybe we should check if GMS is available?
   return GCMClient::SUCCESS;
 }
 
 void GCMDriverAndroid::RegisterImpl(
     const std::string& app_id,
     const std::vector<std::string>& sender_ids) {
   JNIEnv* env = AttachCurrentThread();
   Java_GCMDriver_register(
       env, java_ref_.obj(),
       ConvertUTF8ToJavaString(env, app_id).Release(),
       ToJavaArrayOfStrings(env, sender_ids).obj());
 }
 
 void GCMDriverAndroid::UnregisterImpl(const std::string& app_id) {
   JNIEnv* env = AttachCurrentThread();
   Java_GCMDriver_unregister(
       env, java_ref_.obj(),
       ConvertUTF8ToJavaString(env, app_id).Release());
 }
 
 void GCMDriverAndroid::SendImpl(const std::string& app_id,
                                 const std::string& receiver_id,
                                 const GCMClient::OutgoingMessage& message) {
   NOTIMPLEMENTED();
 }
 
 }  // namespace gcm