Adding an experimental flag to block autoplay with sound in cross-origin iframes

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

 /*
  * Copyright (C) 2007, 2008, 2009, 2010, 2011, 2012, 2013 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
@@ skipping 267 matching lines @@
     case WebMediaPlayer::PreloadMetaData:
       return "metadata";
     case WebMediaPlayer::PreloadAuto:
       return "auto";
   }
 
   NOTREACHED();
   return String();
 }
 
+bool isDocumentCrossOrigin(Document& document) {
+  const LocalFrame* frame = document.frame();
+  return frame && frame->isCrossOriginSubframe();
+}
+
 }  // anonymous namespace
 
 class HTMLMediaElement::AutoplayHelperClientImpl
     : public AutoplayExperimentHelper::Client {
  public:
   static AutoplayHelperClientImpl* create(HTMLMediaElement* element) {
     return new AutoplayHelperClientImpl(element);
   }
 
   virtual ~AutoplayHelperClientImpl();
@@ skipping 25 matching lines @@
     return m_element->isHTMLAudioElement();
   }
 
   // Document
   bool isLegacyViewportType() override;
   PageVisibilityState pageVisibilityState() const override;
   String autoplayExperimentMode() const override;
 
   // Frame
   bool isCrossOrigin() const override {
-    const LocalFrame* frame = m_element->document().frame();
-    return frame && frame->isCrossOriginSubframe();
+    return isDocumentCrossOrigin(m_element->document());
   }
 
   bool isAutoplayAllowedPerSettings() const override;
 
   // LayoutObject
   void setRequestPositionUpdates(bool) override;
   IntRect absoluteBoundingBoxRect() const override;
 
   DEFINE_INLINE_VIRTUAL_TRACE() {
     visitor->trace(m_element);
@@ skipping 117 matching lines @@
       m_autoplayHelperClient(AutoplayHelperClientImpl::create(this)),
       m_autoplayHelper(
           AutoplayExperimentHelper::create(m_autoplayHelperClient.get())),
       m_autoplayUmaHelper(AutoplayUmaHelper::create(this)),
       m_remotePlaybackClient(nullptr),
       m_autoplayVisibilityObserver(nullptr) {
   ThreadState::current()->registerPreFinalizer(this);
 
   BLINK_MEDIA_LOG << "HTMLMediaElement(" << (void*)this << ")";
 
-  // If any experiment is enabled, then we want to enable a user gesture by
-  // default, otherwise the experiment does nothing.
-  if ((document.settings() &&
-       document.settings()->mediaPlaybackRequiresUserGesture()) ||
-      m_autoplayHelper->isExperimentEnabled()) {
-    m_lockedPendingUserGesture = true;
-  }
+  m_lockedPendingUserGesture = computeLockedPendingUserGesture(document);
 
   LocalFrame* frame = document.frame();
   if (frame) {
     m_remotePlaybackClient =
         frame->loader().client()->createWebRemotePlaybackClient(*this);
   }
 
   setHasCustomStyleCallbacks();
   addElementToDocumentMap(this, &document);
 
@@ skipping 23 matching lines @@
   clearMediaPlayerAndAudioSourceProviderClientWithoutLocking();
 }
 
 void HTMLMediaElement::didMoveToNewDocument(Document& oldDocument) {
   BLINK_MEDIA_LOG << "didMoveToNewDocument(" << (void*)this << ")";
 
   m_autoplayUmaHelper->didMoveToNewDocument(oldDocument);
   // If any experiment is enabled, then we want to enable a user gesture by
   // default, otherwise the experiment does nothing.
   bool oldDocumentRequiresUserGesture =
-      (oldDocument.settings() &&
-       oldDocument.settings()->mediaPlaybackRequiresUserGesture()) ||
-      m_autoplayHelper->isExperimentEnabled();
+      computeLockedPendingUserGesture(oldDocument);
   bool newDocumentRequiresUserGesture =
-      (document().settings() &&
-       document().settings()->mediaPlaybackRequiresUserGesture()) ||
-      m_autoplayHelper->isExperimentEnabled();
+      computeLockedPendingUserGesture(document());
   if (newDocumentRequiresUserGesture && !oldDocumentRequiresUserGesture) {
     m_lockedPendingUserGesture = true;
   }
 
   if (m_shouldDelayLoadEvent) {
     document().incrementLoadEventDelayCount();
     // Note: Keeping the load event delay count increment on oldDocument that
     // was added when m_shouldDelayLoadEvent was set so that destruction of
     // m_webMediaPlayer can not cause load event dispatching in oldDocument.
   } else {
@@ skipping 3340 matching lines @@
 
   // Enable the first audio track if an audio track hasn't been enabled yet.
   if (audioTracks().length() > 0 && !audioTracks().hasEnabledTrack())
     audioTracks().anonymousIndexedGetter(0)->setEnabled(true);
 
   // Select the first video track if a video track hasn't been selected yet.
   if (videoTracks().length() > 0 && videoTracks().selectedIndex() == -1)
     videoTracks().anonymousIndexedGetter(0)->setSelected(true);
 }
 
+bool HTMLMediaElement::computeLockedPendingUserGesture(
+    Document& document) const {
+  // TODO(zqzhang): deprecate AutoplayExperiment. See https://crbug.com/666370
+  if (m_autoplayHelper->isExperimentEnabled())
+    return true;
+  if (!document.settings())
+    return false;
+
+  if (document.settings()->crossOriginMediaPlaybackRequiresUserGesture() &&
+      isDocumentCrossOrigin(document))
+    return true;
+
+  return document.settings()->mediaPlaybackRequiresUserGesture();
+}
+
 bool HTMLMediaElement::isLockedPendingUserGesture() const {
   return m_lockedPendingUserGesture;
 }
 
 void HTMLMediaElement::unlockUserGesture() {
   m_lockedPendingUserGesture = false;
 }
 
 bool HTMLMediaElement::isGestureNeededForPlayback() const {
   if (!m_lockedPendingUserGesture)
@@ skipping 288 matching lines @@
 
 IntRect HTMLMediaElement::AutoplayHelperClientImpl::absoluteBoundingBoxRect()
     const {
   IntRect result;
   if (LayoutObject* object = m_element->layoutObject())
     result = object->absoluteBoundingBoxRect();
   return result;
 }
 
 }  // namespace blink