Implement the events for Background Fetch

third_party/WebKit/Source/modules/background_fetch/BackgroundFetchEvent.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/BackgroundFetchEvent.h"
+
+#include "modules/EventModulesNames.h"
+#include "modules/background_fetch/BackgroundFetchEventInit.h"
+
+namespace blink {
+
+BackgroundFetchEvent::BackgroundFetchEvent(const AtomicString& type,
+                                           const BackgroundFetchEventInit& init)
+    : ExtendableEvent(type, init), m_tag(init.tag()) {}
+
+BackgroundFetchEvent::~BackgroundFetchEvent() = default;
+
+String BackgroundFetchEvent::tag() const {
+  return m_tag;
+}
+
+const AtomicString& BackgroundFetchEvent::interfaceName() const {
+  return EventNames::BackgroundFetchEvent;
+}
+
+}  // namespace blink