Add flag for enabling/disabling video fullscreen detection

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 36 matching lines @@
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/ImageBuffer.h"
 #include "platform/graphics/gpu/Extensions3DUtil.h"
 #include "public/platform/WebCanvas.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
 inline HTMLVideoElement::HTMLVideoElement(Document& document)
-    : HTMLMediaElement(videoTag, document),
-      m_customControlsFullscreenDetector(
-          new MediaCustomControlsFullscreenDetector(*this)) {
+    : HTMLMediaElement(videoTag, document) {
   if (document.settings()) {
     m_defaultPosterURL =
         AtomicString(document.settings()->getDefaultVideoPosterURL());
   }
+
+  if (RuntimeEnabledFeatures::videoFullscreenDetectionEnabled()) {
+    m_customControlsFullscreenDetector =
+        new MediaCustomControlsFullscreenDetector(*this);
+  }
 }
 
 HTMLVideoElement* HTMLVideoElement::create(Document& document) {
   HTMLVideoElement* video = new HTMLVideoElement(document);
   video->ensureUserAgentShadowRoot();
   video->suspendIfNeeded();
   return video;
 }
 
 DEFINE_TRACE(HTMLVideoElement) {
@@ skipping 303 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