Eliminate TextTrackCue::updateDisplayTree()

Source/core/html/track/TextTrackCue.h

Index: Source/core/html/track/TextTrackCue.h
diff --git a/Source/core/html/track/TextTrackCue.h b/Source/core/html/track/TextTrackCue.h
index d55d06b555076b540d48a2e341e8f5b404d5dd9d..2c8cc769de0a9a67262aa5e77b5b42c326de29ea 100644
--- a/Source/core/html/track/TextTrackCue.h
+++ b/Source/core/html/track/TextTrackCue.h
@@ -80,12 +80,16 @@ public:
     bool isActive() const { return m_isActive; }
     void setIsActive(bool active) { m_isActive = active; }
 
+    // Updates the display tree and appends it to container if it has not
+    // already been added.
     virtual void updateDisplay(HTMLDivElement& container) = 0;
 
-    // FIXME: Consider refactoring to eliminate or merge the following three members.
-    // https://code.google.com/p/chromium/issues/detail?id=322434
-    virtual void updateDisplayTree(double movieTime) = 0;
+    // Marks the nodes of the display tree as past or future relative to
+    // movieTime. If updateDisplay() has not been called there is no display
+    // tree and nothing is done.
+    virtual void updatePastAndFutureNodes(double movieTime) = 0;
 
+    // FIXME: Refactor to eliminate removeDisplayTree(). https://crbug.com/322434
     enum RemovalNotification {
         DontNotifyRegion,
         NotifyRegion