[Blink, RemotePlayback] watchAvailability() implementation.

third_party/WebKit/Source/modules/remoteplayback/RemotePlaybackAvailability.cpp

-// Copyright 2016 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/remoteplayback/RemotePlaybackAvailability.h"
-
-#include "bindings/core/v8/ScriptPromiseResolver.h"
-#include "core/dom/Document.h"
-#include "core/events/Event.h"
-#include "modules/EventTargetModulesNames.h"
-
-namespace blink {
-
-// static
-RemotePlaybackAvailability* RemotePlaybackAvailability::take(
-    ScriptPromiseResolver* resolver,
-    bool value) {
-  return new RemotePlaybackAvailability(resolver->getExecutionContext(), value);
-}
-
-RemotePlaybackAvailability::RemotePlaybackAvailability(
-    ExecutionContext* executionContext,
-    bool value)
-    : ActiveScriptWrappable(this),
-      ContextLifecycleObserver(executionContext),
-      m_value(value) {
-  ASSERT(executionContext->isDocument());
-}
-
-RemotePlaybackAvailability::~RemotePlaybackAvailability() = default;
-
-const AtomicString& RemotePlaybackAvailability::interfaceName() const {
-  return EventTargetNames::RemotePlaybackAvailability;
-}
-
-ExecutionContext* RemotePlaybackAvailability::getExecutionContext() const {
-  return ContextLifecycleObserver::getExecutionContext();
-}
-
-void RemotePlaybackAvailability::availabilityChanged(bool value) {
-  if (m_value == value)
-    return;
-
-  m_value = value;
-  dispatchEvent(Event::create(EventTypeNames::change));
-}
-
-bool RemotePlaybackAvailability::value() const {
-  return m_value;
-}
-
-bool RemotePlaybackAvailability::hasPendingActivity() const {
-  return hasEventListeners();
-}
-
-DEFINE_TRACE(RemotePlaybackAvailability) {
-  EventTargetWithInlineData::trace(visitor);
-  ContextLifecycleObserver::trace(visitor);
-}
-
-}  // namespace blink