Media Remoting: Add interstitial elements to media element shadow dom.

third_party/WebKit/Source/core/html/shadow/MediaRemotingInterstitial.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 "core/html/shadow/MediaRemotingInterstitial.h"
+
+#include "core/html/HTMLMediaElement.h"
+#include "core/html/shadow/MediaControlElements.h"
+
+namespace blink {
+
+MediaRemotingInterstitial::MediaRemotingInterstitial(
+    HTMLMediaElement& mediaElement)
+    : HTMLDivElement(mediaElement.document()), m_mediaElement(&mediaElement) {
+  setShadowPseudoId(AtomicString("-webkit-media-remoting-interstitial"));
+  m_mediaRemotingDisableButton = new MediaRemotingDisableButtonElement(*this);
+  appendChild(m_mediaRemotingDisableButton);
+}
+
+void MediaRemotingInterstitial::show() {
+  m_mediaRemotingDisableButton->show();
+}
+
+void MediaRemotingInterstitial::hide() {
+  m_mediaRemotingDisableButton->hide();
+}
+
+DEFINE_TRACE(MediaRemotingInterstitial) {
+  visitor->trace(m_mediaElement);
+  visitor->trace(m_mediaRemotingDisableButton);
+  HTMLDivElement::trace(visitor);
+}
+
+}  // namespace blink