Tweak the TextTrackCue "cue index" management

Source/core/html/track/TextTrackCue.cpp

 /*
  * Copyright (C) 2011 Google Inc.  All rights reserved.
  * Copyright (C) 2011, 2012, 2013 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 22 matching lines @@
 #include "core/html/track/TextTrackCue.h"
 
 #include "bindings/core/v8/ExceptionMessages.h"
 #include "bindings/core/v8/ExceptionStatePlaceholder.h"
 #include "core/events/Event.h"
 #include "core/html/track/TextTrack.h"
 #include "core/html/track/TextTrackCueList.h"
 
 namespace blink {
 
-static const int invalidCueIndex = -1;
+static const unsigned invalidCueIndex = UINT_MAX;
 
 TextTrackCue::TextTrackCue(double start, double end)
     : m_startTime(start)
     , m_endTime(end)
+    , m_track(nullptr)
     , m_cueIndex(invalidCueIndex)
-    , m_track(nullptr)
     , m_isActive(false)
     , m_pauseOnExit(false)
 {
 }
 
 void TextTrackCue::cueWillChange()
 {
     if (m_track)
         m_track->cueWillChange(this);
 }
@@ skipping 54 matching lines @@
 void TextTrackCue::setPauseOnExit(bool value)
 {
     if (m_pauseOnExit == value)
         return;
 
     cueWillChange();
     m_pauseOnExit = value;
     cueDidChange();
 }
 
-int TextTrackCue::cueIndex()
-{
-    if (m_cueIndex == invalidCueIndex)
-        m_cueIndex = track()->cues()->getCueIndex(this);
-
-    return m_cueIndex;
-}
-
 void TextTrackCue::invalidateCueIndex()
 {
     m_cueIndex = invalidCueIndex;
 }
 
+unsigned TextTrackCue::cueIndex()
+{
+    // This method can only be called on cues while they are associated with
+    // a(n enabled) track (and hence that track's list of cues should exist.)
+    ASSERT(track() && track()->cues());
+    TextTrackCueList* cueList = track()->cues();
+    if (!cueList->isCueIndexValid(m_cueIndex))
+        cueList->validateCueIndexes();
+    return m_cueIndex;
+}
+
 bool TextTrackCue::dispatchEvent(PassRefPtrWillBeRawPtr<Event> event)
 {
     // When a TextTrack's mode is disabled: no cues are active, no events fired.
     if (!track() || track()->mode() == TextTrack::disabledKeyword())
         return false;
 
     return EventTarget::dispatchEvent(event);
 }
 
 bool TextTrackCue::isActive()
 {
     return m_isActive && track() && track()->mode() != TextTrack::disabledKeyword();
 }
 
 const AtomicString& TextTrackCue::interfaceName() const
 {
     return EventTargetNames::TextTrackCue;
 }
 
 DEFINE_TRACE(TextTrackCue)
 {
     visitor->trace(m_track);
     EventTargetWithInlineData::trace(visitor);
 }
 
 } // namespace blink