Changing <video> src during 'ended' event can leave screen sleep disa…

…bled

https://bugs.webkit.org/show_bug.cgi?id=152018

Reviewed by Eric Carlson.

Resetting a HTMLMediaElement's src during 'ended' introduces a race condition: whether
the 'mediaPlayerRateChanged()' notification will fire before createMediaPlayer() destroys
the old MediaPlayer firing said notification.

To break the race condition, always update the sleep disabling assertion after destroying
the media player (by creating a new one).

* html/HTMLMediaElement.cpp:
(WebCore::HTMLMediaElement::createMediaPlayer):


Canonical link: https://commits.webkit.org/170177@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@193798 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebCore/ChangeLog

@@ -1,3 +1,20 @@
+2015-12-08  Jer Noble  <jer.noble@apple.com>
+
+        Changing <video> src during 'ended' event can leave screen sleep disabled
+        https://bugs.webkit.org/show_bug.cgi?id=152018
+
+        Reviewed by Eric Carlson.
+
+        Resetting a HTMLMediaElement's src during 'ended' introduces a race condition: whether
+        the 'mediaPlayerRateChanged()' notification will fire before createMediaPlayer() destroys
+        the old MediaPlayer firing said notification.
+
+        To break the race condition, always update the sleep disabling assertion after destroying
+        the media player (by creating a new one).
+
+        * html/HTMLMediaElement.cpp:
+        (WebCore::HTMLMediaElement::createMediaPlayer):
+
 2015-12-08  Brady Eidson  <beidson@apple.com>
 
         Modern IDB: Fire blocked events for delete requests that are blocked.

Source/WebCore/html/HTMLMediaElement.cpp

@@ -5790,6 +5790,8 @@ void HTMLMediaElement::createMediaPlayer()
         enqueuePlaybackTargetAvailabilityChangedEvent(); // Ensure the event listener gets at least one event.
     }
 #endif
+
+    updateSleepDisabling();
 }
 
 #if ENABLE(WEB_AUDIO)