Service Worker: Respect the "clear on exit" content setting

content/browser/service_worker/service_worker_database_task_manager.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/sequenced_task_runner.h"
+#include "base/threading/sequenced_worker_pool.h"
+#include "content/browser/service_worker/service_worker_database_task_manager.h"
+
+namespace content {
+
+namespace {
+
+const char kServiceWorkerDatabaseTaskSequenceTokenName[] =
+    "service-worker-database-task-token";
+
+}  // namespace
+
+ServiceWorkerDatabaseTaskManagerImpl::ServiceWorkerDatabaseTaskManagerImpl(
+    base::SequencedWorkerPool* pool)
+    : pool_(pool) {
+  base::SequencedWorkerPool::SequenceToken token =
+      pool->GetNamedSequenceToken(kServiceWorkerDatabaseTaskSequenceTokenName);

[michaeln, 2014/10/16 01:15:04]

In the existing code, each swcontext uses a unique token. Is there a reason to
alter that existing behavior by using the same named token for all swcontexts?
If not, probably should continue to use a unique token per-context. So tasks
from different swcontexts don't impede one another.
 token = pool->GetSequenceToken();

[falken, 2014/10/16 02:04:51]

Good point! Done.

+  task_runner_ = pool_->GetSequencedTaskRunner(token);
+  shutdown_blocking_task_runner_ =
+      pool_->GetSequencedTaskRunnerWithShutdownBehavior(
+          token, base::SequencedWorkerPool::BLOCK_SHUTDOWN);
+}
+
+ServiceWorkerDatabaseTaskManagerImpl::~ServiceWorkerDatabaseTaskManagerImpl() {
+}
+
+scoped_ptr<ServiceWorkerDatabaseTaskManager>
+ServiceWorkerDatabaseTaskManagerImpl::Clone() {
+  return make_scoped_ptr(new ServiceWorkerDatabaseTaskManagerImpl(pool_.get()));
+}
+
+base::SequencedTaskRunner*
+ServiceWorkerDatabaseTaskManagerImpl::GetTaskRunner() {
+  return task_runner_.get();
+}
+
+base::SequencedTaskRunner*
+ServiceWorkerDatabaseTaskManagerImpl::GetShutdownBlockingTaskRunner() {
+  return shutdown_blocking_task_runner_.get();
+}
+
+MockServiceWorkerDatabaseTaskManager::MockServiceWorkerDatabaseTaskManager(
+    const scoped_refptr<base::SequencedTaskRunner>& task_runner)
+    : task_runner_(task_runner) {
+}
+
+MockServiceWorkerDatabaseTaskManager::~MockServiceWorkerDatabaseTaskManager() {
+}
+
+scoped_ptr<ServiceWorkerDatabaseTaskManager>
+MockServiceWorkerDatabaseTaskManager::Clone() {
+  return make_scoped_ptr(
+      new MockServiceWorkerDatabaseTaskManager(task_runner_));
+}
+
+base::SequencedTaskRunner*
+MockServiceWorkerDatabaseTaskManager::GetTaskRunner() {
+  return task_runner_.get();
+}
+
+base::SequencedTaskRunner*
+MockServiceWorkerDatabaseTaskManager::GetShutdownBlockingTaskRunner() {
+  return task_runner_.get();
+}
+
+}  // namespace content