Merge WebKit r153448 (Optimizes the number of updateTextTrackDisplay calls)

Source/core/html/HTMLMediaElement.cpp

Index: Source/core/html/HTMLMediaElement.cpp
diff --git a/Source/core/html/HTMLMediaElement.cpp b/Source/core/html/HTMLMediaElement.cpp
index 85ecc7663bee2719647c9eb645e2269f605e9f09..3794196f81d4d7a939283de2830aaf795e22d53f 100644
--- a/Source/core/html/HTMLMediaElement.cpp
+++ b/Source/core/html/HTMLMediaElement.cpp
@@ -1031,16 +1031,8 @@ void HTMLMediaElement::updateActiveTextTrackCues(double movieTime)
             activeSetChanged = true;
     }
 
-    if (!activeSetChanged) {
-        // Even though the active set has not changed, it is possible that the
-        // the mode of a track has changed from 'hidden' to 'showing' and the
-        // cues have not yet been rendered.
-        // Note: don't call updateTextTrackDisplay() unless we have controls because it will
-        // create them.
-        if (hasMediaControls())

[acolwell GONE FROM CHROMIUM, 2013/08/12 20:19:02]

Why is this code dropped? Doesn't this result in a behavior change?

[vcarbune.chromium, 2013/08/19 22:20:12]

No, configureTextTrackDisplay now calls this if AssumeVisibleChange is passed. I
added a while ago this code and it's covered by
track-cue-rendering-mode-changed, which passes using the optimizations.

-            updateTextTrackDisplay();
+    if (!activeSetChanged)
         return;
-    }
 
     // 7 - If the time was reached through the usual monotonic increase of the
     // current playback position during normal playback, and there are cues in
@@ -1241,8 +1233,7 @@ void HTMLMediaElement::textTrackModeChanged(TextTrack* track)
     } else if (track->trackType() == TextTrack::AddTrack && track->mode() != TextTrack::disabledKeyword())
         textTrackAddCues(track, track->cues());
 
-    configureTextTrackDisplay();
-    updateActiveTextTrackCues(currentTime());
+    configureTextTrackDisplay(AssumeVisibleTextTracksChanged);
 }
 
 void HTMLMediaElement::textTrackKindChanged(TextTrack* track)
@@ -3710,7 +3701,7 @@ void HTMLMediaElement::configureMediaControls()
     mediaControls()->show();
 }
 
-void HTMLMediaElement::configureTextTrackDisplay()
+void HTMLMediaElement::configureTextTrackDisplay(ConfigureTextTrackDisplayFlags flags)
 {
     ASSERT(m_textTracks);
     LOG(Media, "HTMLMediaElement::configureTextTrackDisplay");
@@ -3726,8 +3717,11 @@ void HTMLMediaElement::configureTextTrackDisplay()
         }
     }
 
-    if (m_haveVisibleTextTrack == haveVisibleTextTrack)
+    if (flags == DoNotAssumeVisibleTextTracksChanged
+        && m_haveVisibleTextTrack == haveVisibleTextTrack) {
+        updateActiveTextTrackCues(currentTime());
         return;
+    }
     m_haveVisibleTextTrack = haveVisibleTextTrack;
     m_closedCaptionsVisible = m_haveVisibleTextTrack;