Push API: Validate storage before returning cached subscriptions

components/gcm_driver/instance_id/instance_id_android.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/instance_id_android.h"
 
 #include <stdint.h>
 
 #include <memory>
 
@@ skipping 103 matching lines @@
   }
 
   JNIEnv* env = AttachCurrentThread();
   Java_InstanceIDBridge_getToken(
       env, java_ref_, request_id,
       ConvertUTF8ToJavaString(env, authorized_entity),
       ConvertUTF8ToJavaString(env, scope),
       base::android::ToJavaArrayOfStrings(env, options_strings));
 }
 
+void InstanceIDAndroid::ValidateToken(const std::string& authorized_entity,
+                                      const std::string& scope,
+                                      const std::string& token,
+                                      const ValidateTokenCallback& callback) {
+  // gcm_driver doesn't store tokens on Android, so assume it's valid.
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::Bind(callback, true /* is_valid */));
+}
+
 void InstanceIDAndroid::DeleteTokenImpl(const std::string& authorized_entity,
                                         const std::string& scope,
                                         const DeleteTokenCallback& callback) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   int32_t request_id = delete_token_callbacks_.Add(
       base::MakeUnique<DeleteTokenCallback>(callback));
 
   JNIEnv* env = AttachCurrentThread();
   Java_InstanceIDBridge_deleteToken(
@@ skipping 82 matching lines @@
     jboolean success) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   DeleteIDCallback* callback = delete_id_callbacks_.Lookup(request_id);
   DCHECK(callback);
   callback->Run(success ? InstanceID::SUCCESS : InstanceID::UNKNOWN_ERROR);
   delete_id_callbacks_.Remove(request_id);
 }
 
 }  // namespace instance_id