Fix an issue in fullscreen detector when context is destroyed

third_party/WebKit/Source/core/html/HTMLVideoElement.cpp

 /*
  * Copyright (C) 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 58 matching lines @@
   video->suspendIfNeeded();
   return video;
 }
 
 DEFINE_TRACE(HTMLVideoElement) {
   visitor->trace(m_imageLoader);
   visitor->trace(m_customControlsFullscreenDetector);
   HTMLMediaElement::trace(visitor);
 }
 
+void HTMLVideoElement::contextDestroyed(ExecutionContext* context) {
+  m_customControlsFullscreenDetector->contextDestroyed();
+  HTMLMediaElement::contextDestroyed(context);
+}
+
 bool HTMLVideoElement::layoutObjectIsNeeded(const ComputedStyle& style) {
   return HTMLElement::layoutObjectIsNeeded(style);
 }
 
 LayoutObject* HTMLVideoElement::createLayoutObject(const ComputedStyle&) {
   return new LayoutVideo(this);
 }
 
 void HTMLVideoElement::attachLayoutTree(const AttachContext& context) {
   HTMLMediaElement::attachLayoutTree(context);
@@ skipping 288 matching lines @@
     return ScriptPromise();
   if (!ImageBitmap::isResizeOptionValid(options, exceptionState))
     return ScriptPromise();
   return ImageBitmapSource::fulfillImageBitmap(
       scriptState,
       ImageBitmap::create(this, cropRect,
                           eventTarget.toLocalDOMWindow()->document(), options));
 }
 
 }  // namespace blink