Fix HTMLMediaElement to always use the 'effective playback rate'

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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 2098 matching lines @@
 void HTMLMediaElement::setPlaybackRate(double rate)
 {
     WTF_LOG(Media, "HTMLMediaElement::setPlaybackRate(%f)", rate);
 
     if (m_playbackRate != rate) {
         m_playbackRate = rate;
         invalidateCachedTime();
         scheduleEvent(EventTypeNames::ratechange);
     }
 
-    if (m_player && potentiallyPlaying() && m_player->rate() != rate && !m_mediaController)
-        m_player->setRate(rate);
+    updatePlaybackRate();
+}
+
+double HTMLMediaElement::effectivePlaybackRate() const
+{
+    return m_mediaController ? m_mediaController->playbackRate() : m_playbackRate;
 }
 
 HTMLMediaElement::DirectionOfPlayback HTMLMediaElement::directionOfPlayback() const
 {
     return m_playbackRate >= 0 ? Forward : Backward;
 }
 
 void HTMLMediaElement::updatePlaybackRate()
 {
-    double effectiveRate = m_mediaController ? m_mediaController->playbackRate() : m_playbackRate;
+    double effectiveRate = effectivePlaybackRate();
     if (m_player && potentiallyPlaying() && m_player->rate() != effectiveRate)
         m_player->setRate(effectiveRate);
 }
 
 bool HTMLMediaElement::ended() const
 {
     // 4.8.10.8 Playing the media resource
     // The ended attribute must return true if the media element has ended
     // playback and the direction of playback is forwards, and false otherwise.
     return endedPlayback() && directionOfPlayback() == Forward;
@@ skipping 192 matching lines @@
         if (!m_mediaController && !m_paused) {
             UseCounter::count(document(), UseCounter::HTMLMediaElementPauseAtFragmentEnd);
             // changes paused to true and fires a simple event named pause at the media element.
             pause();
         }
     }
 
     if (!m_seeking)
         scheduleTimeupdateEvent(true);
 
-    if (!m_playbackRate)
+    if (!effectivePlaybackRate())
         return;
 
     if (!m_paused && hasMediaControls())
         mediaControls()->playbackProgressed();
 
     updateActiveTextTrackCues(currentTime());
 }
 
 void HTMLMediaElement::scheduleTimeupdateEvent(bool periodicEvent)
 {
@@ skipping 914 matching lines @@
     WTF_LOG(Media, "HTMLMediaElement::updatePlayState - shouldBePlaying = %s, playerPaused = %s",
         boolString(shouldBePlaying), boolString(playerPaused));
 
     if (shouldBePlaying) {
         setDisplayMode(Video);
         invalidateCachedTime();
 
         if (playerPaused) {
             // Set rate, muted before calling play in case they were set before the media engine was setup.
             // The media engine should just stash the rate and muted values since it isn't already playing.
-            m_player->setRate(m_playbackRate);
+            m_player->setRate(effectivePlaybackRate());
             updateVolume();
 
             m_player->play();
         }
 
         if (hasMediaControls())
             mediaControls()->playbackStarted();
         startPlaybackProgressTimer();
         m_playing = true;
 
@@ skipping 661 matching lines @@
 
 #if ENABLE(WEB_AUDIO)
 void HTMLMediaElement::clearWeakMembers(Visitor* visitor)
 {
     if (!visitor->isAlive(m_audioSourceNode) && audioSourceProvider())
         audioSourceProvider()->setClient(0);
 }
 #endif
 
 }