Stop pushing the value of 'default' to LoadableTextTrack

Source/core/html/track/LoadableTextTrack.cpp

Index: Source/core/html/track/LoadableTextTrack.cpp
diff --git a/Source/core/html/track/LoadableTextTrack.cpp b/Source/core/html/track/LoadableTextTrack.cpp
index 35cf8f5a8f67d8c6040c1e881dcb4480a88d10a9..2e16d2ae09a006654d7625d8a9fbab38a3e868c6 100644
--- a/Source/core/html/track/LoadableTextTrack.cpp
+++ b/Source/core/html/track/LoadableTextTrack.cpp
@@ -39,7 +39,6 @@ LoadableTextTrack::LoadableTextTrack(HTMLTrackElement* track)
     : TextTrack(emptyAtom, emptyAtom, emptyAtom, emptyAtom, TrackElement)
     , m_trackElement(track)
     , m_loadTimer(this, &LoadableTextTrack::loadTimerFired)
-    , m_isDefault(false)
 {
 }
 
@@ -57,6 +56,12 @@ void LoadableTextTrack::clearTrackElement()
 }
 #endif
 
+bool LoadableTextTrack::isDefault() const
+{
+    ASSERT(m_trackElement);
+    return m_trackElement->fastHasAttribute(defaultAttr);
+}
+
 void LoadableTextTrack::setMode(const AtomicString& mode)
 {
     TextTrack::setMode(mode);