Provide a WebContents API to discover the playback of a fullscreen video.

media/blink/webmediaplayer_impl.cc

 // Copyright 2013 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 "media/blink/webmediaplayer_impl.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 #include <string>
@@ skipping 338 matching lines @@
 void WebMediaPlayerImpl::enteredFullscreen() {
   // |force_video_overlays_| implies that we're already in overlay mode, so take
   // no action here.  Otherwise, switch to an overlay if it's allowed and if
   // it will display properly.
   if (!force_video_overlays_ && enable_fullscreen_video_overlays_ &&
       DoesOverlaySupportMetadata()) {
     EnableOverlay();
   }
   if (observer_)
     observer_->OnEnteredFullscreen();
+  delegate_->SetIsEffectivelyFullscreen(delegate_id_, true);
 }
 
 void WebMediaPlayerImpl::exitedFullscreen() {
   // If we're in overlay mode, then exit it unless we're supposed to be in
   // overlay mode all the time.
   if (!force_video_overlays_ && overlay_enabled_)
     DisableOverlay();
   if (observer_)
     observer_->OnExitedFullscreen();
+  delegate_->SetIsEffectivelyFullscreen(delegate_id_, false);
 }
 
 void WebMediaPlayerImpl::becameDominantVisibleContent(bool isDominant) {
   if (observer_)
     observer_->OnBecameDominantVisibleContent(isDominant);
 }
 
 void WebMediaPlayerImpl::DoLoad(LoadType load_type,
                                 const blink::WebURL& url,
                                 CORSMode cors_mode) {
@@ skipping 1917 matching lines @@
 
 void WebMediaPlayerImpl::RecordUnderflowDuration(base::TimeDelta duration) {
   DCHECK(data_source_ || chunk_demuxer_);
   if (data_source_)
     UMA_HISTOGRAM_TIMES("Media.UnderflowDuration", duration);
   else
     UMA_HISTOGRAM_TIMES("Media.UnderflowDuration.MSE", duration);
 }
 
 }  // namespace media