Push API: Validate storage before returning cached subscriptions

components/gcm_driver/instance_id/fake_gcm_driver_for_instance_id.cc

 // Copyright 2015 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/instance_id/fake_gcm_driver_for_instance_id.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/rand_util.h"
 #include "base/single_thread_task_runner.h"
@@ skipping 60 matching lines @@
     tokens_[key] = token;
   }
 
   last_gettoken_app_id_ = app_id;
   last_gettoken_authorized_entity_ = authorized_entity;
 
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(callback, token, gcm::GCMClient::SUCCESS));
 }
 
+void FakeGCMDriverForInstanceID::ValidateToken(
+    const std::string& app_id,
+    const std::string& authorized_entity,
+    const std::string& scope,
+    const std::string& token,
+    const ValidateTokenCallback& callback) {
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::Bind(callback, true /* is_valid */));
+}
+
 void FakeGCMDriverForInstanceID::DeleteToken(
     const std::string& app_id,
     const std::string& authorized_entity,
     const std::string& scope,
     const DeleteTokenCallback& callback) {
   std::string key = app_id + authorized_entity + scope;
   tokens_.erase(key);
 
   last_deletetoken_app_id_ = app_id;
 
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(callback, gcm::GCMClient::SUCCESS));
 }
 
 }  // namespace instance_id