Introduce the Background Fetch module.

third_party/WebKit/Source/modules/background_fetch/ServiceWorkerRegistrationBackgroundFetch.cpp

+// Copyright 2017 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 "modules/background_fetch/ServiceWorkerRegistrationBackgroundFetch.h"
+
+#include "modules/background_fetch/BackgroundFetchManager.h"
+
+namespace blink {
+
+ServiceWorkerRegistrationBackgroundFetch::
+    ServiceWorkerRegistrationBackgroundFetch(
+        ServiceWorkerRegistration* registration)
+    : m_registration(registration) {}
+
+ServiceWorkerRegistrationBackgroundFetch::
+    ~ServiceWorkerRegistrationBackgroundFetch() = default;
+
+const char* ServiceWorkerRegistrationBackgroundFetch::supplementName() {
+  return "ServiceWorkerRegistrationBackgroundFetch";
+}
+
+ServiceWorkerRegistrationBackgroundFetch&
+ServiceWorkerRegistrationBackgroundFetch::from(
+    ServiceWorkerRegistration& registration) {
+  ServiceWorkerRegistrationBackgroundFetch* supplement =
+      static_cast<ServiceWorkerRegistrationBackgroundFetch*>(
+          Supplement<ServiceWorkerRegistration>::from(registration,
+                                                      supplementName()));
+
+  if (!supplement) {
+    supplement = new ServiceWorkerRegistrationBackgroundFetch(&registration);
+    provideTo(registration, supplementName(), supplement);
+  }
+
+  return *supplement;
+}
+
+BackgroundFetchManager*
+ServiceWorkerRegistrationBackgroundFetch::backgroundFetch(
+    ServiceWorkerRegistration& registration) {
+  return ServiceWorkerRegistrationBackgroundFetch::from(registration)
+      .backgroundFetch();
+}
+
+BackgroundFetchManager*
+ServiceWorkerRegistrationBackgroundFetch::backgroundFetch() {
+  if (!m_backgroundFetchManager)
+    m_backgroundFetchManager = BackgroundFetchManager::create(m_registration);
+
+  return m_backgroundFetchManager.get();
+}
+
+DEFINE_TRACE(ServiceWorkerRegistrationBackgroundFetch) {
+  visitor->trace(m_registration);
+  visitor->trace(m_backgroundFetchManager);
+  Supplement<ServiceWorkerRegistration>::trace(visitor);
+}
+
+}  // namespace blink