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

content/renderer/render_view_impl.cc

 // Copyright (c) 2012 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 "content/renderer/render_view_impl.h"
 
 #include <algorithm>
 #include <cmath>
 #include <memory>
 
@@ skipping 1135 matching lines @@
           prefs.progress_bar_completion));
   settings->setPreferHiddenVolumeControls(true);
 
   // Force preload=none and disable autoplay on older or low end Android
   // platforms because their media pipelines are not stable enough to handle
   // concurrent elements. See http://crbug.com/612909, http://crbug.com/622826.
   const bool is_low_end_device =
       base::android::BuildInfo::GetInstance()->sdk_int() <=
           base::android::SDK_VERSION_JELLY_BEAN_MR2 ||
       base::SysInfo::IsLowEndDevice();
-  settings->setForcePreloadNoneForMediaElements(is_low_end_device);
   WebRuntimeFeatures::enableAutoplayMutedVideos(
       prefs.autoplay_muted_videos_enabled && !is_low_end_device);
+  settings->setForcePreloadNoneForMediaElements(is_low_end_device);
   settings->setSpellCheckEnabledByDefault(prefs.spellcheck_enabled_by_default);
+#else
+  WebRuntimeFeatures::enableAutoplayMutedVideos(
+      prefs.autoplay_muted_videos_enabled);
+#endif
+
+#if !defined(OS_ANDROID)
+  settings->setMediaPlaybackInCrossOriginIframesRequiresUserGesture(
+      prefs.user_gesture_required_for_media_playback_in_cross_origin_iframes);
 #endif
 
   settings->setAutoplayExperimentMode(
       blink::WebString::fromUTF8(prefs.autoplay_experiment_mode));
 
   settings->setViewportEnabled(prefs.viewport_enabled);
   settings->setViewportMetaEnabled(prefs.viewport_meta_enabled);
   settings->setShrinksViewportContentToFit(
         prefs.shrinks_viewport_contents_to_fit);
   settings->setViewportStyle(
@@ skipping 1794 matching lines @@
                             INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   }
 
   std::unique_ptr<InputEventAck> ack(
       new InputEventAck(InputEventAckSource::MAIN_THREAD, input_event->type,
                         INPUT_EVENT_ACK_STATE_NOT_CONSUMED));
   OnInputEventAck(std::move(ack));
 }
 
 }  // namespace content