Fix HTMLMediaElement so that it doesn't add cues for disabled text tracks.

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 7ae83aebde141b42b4a19eccf9140177ce630d31..218315ed24406dd055c7d0b331ed9dd88af6fb48 100644
--- a/Source/core/html/HTMLMediaElement.cpp
+++ b/Source/core/html/HTMLMediaElement.cpp
@@ -1262,9 +1262,10 @@ void HTMLMediaElement::endIgnoringTrackDisplayUpdateRequests()
         updateActiveTextTrackCues(currentTime());
 }
 
-void HTMLMediaElement::textTrackAddCues(TextTrack*, const TextTrackCueList* cues)
+void HTMLMediaElement::textTrackAddCues(TextTrack* track, const TextTrackCueList* cues)
 {
     LOG(Media, "HTMLMediaElement::textTrackAddCues");
+    ASSERT(track->mode() != TextTrack::disabledKeyword());

[adamk, 2013/07/08 19:16:38]

Not sure if we have any compilers that actually complain about unused arguments,
but for consistency I think this should use

ASSERT_UNUSED(track, ...);

[acolwell GONE FROM CHROMIUM, 2013/07/08 19:25:48]

Done.

 
     TrackDisplayUpdateScope scope(this);
     for (size_t i = 0; i < cues->length(); ++i)