Stop pushing the value of 'default' to LoadableTextTrack

Source/core/html/HTMLTrackElement.cpp

Index: Source/core/html/HTMLTrackElement.cpp
diff --git a/Source/core/html/HTMLTrackElement.cpp b/Source/core/html/HTMLTrackElement.cpp
index 09187eca5231221b7a844cdbca4a570788f35049..3a0871731d4353a86ac37e08e7e5b6eb71140730 100644
--- a/Source/core/html/HTMLTrackElement.cpp
+++ b/Source/core/html/HTMLTrackElement.cpp
@@ -105,8 +105,6 @@ void HTMLTrackElement::parseAttribute(const QualifiedName& name, const AtomicStr
         track()->setLanguage(value);
     } else if (name == idAttr) {
         track()->setId(value);
-    } else if (name == defaultAttr) {
-        track()->setIsDefault(!value.isNull());
     }
 
     HTMLElement::parseAttribute(name, value);