Remove TextTrackClient interface to simplify TextTrack code.

Source/core/html/track/TextTrack.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 77 matching lines @@
     DEFINE_STATIC_LOCAL(const AtomicString, closed, ("hidden", AtomicString::ConstructFromLiteral));
     return closed;
 }
 
 const AtomicString& TextTrack::showingKeyword()
 {
     DEFINE_STATIC_LOCAL(const AtomicString, ended, ("showing", AtomicString::ConstructFromLiteral));
     return ended;
 }
 
-TextTrack::TextTrack(Document& document, TextTrackClient* client, const AtomicString& kind, const AtomicString& label, const AtomicString& language, const AtomicString& id, TextTrackType type)
+TextTrack::TextTrack(Document& document, const AtomicString& kind, const AtomicString& label, const AtomicString& language, const AtomicString& id, TextTrackType type)
     : TrackBase(TrackBase::TextTrack, label, language, id)
     , m_cues(nullptr)
     , m_regions(nullptr)
     , m_document(&document)
     , m_trackList(0)
     , m_mode(disabledKeyword())
-    , m_client(client)
     , m_trackType(type)
     , m_readinessState(NotLoaded)
     , m_trackIndex(invalidTrackIndex)
     , m_renderedTrackIndex(invalidTrackIndex)
     , m_hasBeenConfigured(false)
 {
     ScriptWrappable::init(this);
     setKind(kind);
 }
 
 TextTrack::~TextTrack()
 {
+    ASSERT(!m_trackList);
+
     if (m_cues) {
-        if (m_client)
-            m_client->textTrackRemoveCues(this, m_cues.get());
-
         for (size_t i = 0; i < m_cues->length(); ++i)
             m_cues->item(i)->setTrack(0);
     }
 
     if (m_regions) {
         for (size_t i = 0; i < m_regions->length(); ++i)
             m_regions->item(i)->setTrack(0);
     }
-    clearClient();
 }
 
 bool TextTrack::isValidKindKeyword(const AtomicString& value)
 {
     if (value == subtitlesKeyword())
         return true;
     if (value == captionsKeyword())
         return true;
     if (value == descriptionsKeyword())
         return true;
     if (value == chaptersKeyword())
         return true;
     if (value == metadataKeyword())
         return true;
 
     return false;
 }
 
 void TextTrack::setTrackList(TextTrackList* trackList)
 {
-    // NOTE: We are using m_trackList->owner() instead of m_client here because
-    // when a HTMLTrackElement is reparented, HTMLTrackElement::textTrackRemoveCues()
-    // will forward the call to the new parent instead of the element the track is being
-    // removed from.
-    if (!trackList && m_trackList && m_trackList->owner() && m_cues)
-        m_trackList->owner()->textTrackRemoveCues(this, m_cues.get());
+    if (!trackList && mediaElement() && m_cues)
+        mediaElement()->textTrackRemoveCues(this, m_cues.get());
+
     m_trackList = trackList;
 }
 
 void TextTrack::setKind(const AtomicString& newKind)
 {
     AtomicString oldKind = kind();
     TrackBase::setKind(newKind);
 
-    if (m_client && oldKind != kind())
-        m_client->textTrackKindChanged(this);
+    if (mediaElement() && oldKind != kind())
+        mediaElement()->textTrackKindChanged(this);
 }
 
 void TextTrack::setMode(const AtomicString& mode)
 {
     ASSERT(mode == disabledKeyword() || mode == hiddenKeyword() || mode == showingKeyword());
 
     // On setting, if the new value isn't equal to what the attribute would currently
     // return, the new value must be processed as follows ...
     if (m_mode == mode)
         return;
 
     // If mode changes to disabled, remove this track's cues from the client
     // because they will no longer be accessible from the cues() function.
-    if (mode == disabledKeyword() && m_client && m_cues)
-        m_client->textTrackRemoveCues(this, m_cues.get());
+    if (mode == disabledKeyword() && mediaElement() && m_cues)
+        mediaElement()->textTrackRemoveCues(this, m_cues.get());
 
     if (mode != showingKeyword() && m_cues)
         for (size_t i = 0; i < m_cues->length(); ++i)
             m_cues->item(i)->removeDisplayTree();
 
     m_mode = mode;
 
-    if (m_client)
-        m_client->textTrackModeChanged(this);
+    if (mediaElement())
+        mediaElement()->textTrackModeChanged(this);
 }
 
 TextTrackCueList* TextTrack::cues()
 {
     // 4.8.10.12.5 If the text track mode ... is not the text track disabled mode,
     // then the cues attribute must return a live TextTrackCueList object ...
     // Otherwise, it must return null. When an object is returned, the
     // same object must be returned each time.
     // http://www.whatwg.org/specs/web-apps/current-work/#dom-texttrack-cues
     if (m_mode != disabledKeyword())
         return ensureTextTrackCueList();
     return 0;
 }
 
 void TextTrack::removeAllCues()
 {
     if (!m_cues)
         return;
 
-    if (m_client)
-        m_client->textTrackRemoveCues(this, m_cues.get());
+    if (mediaElement())
+        mediaElement()->textTrackRemoveCues(this, m_cues.get());
 
     for (size_t i = 0; i < m_cues->length(); ++i)
         m_cues->item(i)->setTrack(0);
 
     m_cues = nullptr;
 }
 
 TextTrackCueList* TextTrack::activeCues() const
 {
     // 4.8.10.12.5 If the text track mode ... is not the text track disabled mode,
@@ skipping 25 matching lines @@
     // 1. If the given cue is in a text track list of cues, then remove cue from that text track
     // list of cues.
     TextTrack* cueTrack = cue->track();
     if (cueTrack && cueTrack != this)
         cueTrack->removeCue(cue.get(), ASSERT_NO_EXCEPTION);
 
     // 2. Add cue to the method's TextTrack object's text track's text track list of cues.
     cue->setTrack(this);
     ensureTextTrackCueList()->add(cue);
 
-    if (m_client)
-        m_client->textTrackAddCue(this, cue.get());
+    if (mediaElement())
+        mediaElement()->textTrackAddCue(this, cue.get());
 }
 
 void TextTrack::removeCue(TextTrackCue* cue, ExceptionState& exceptionState)
 {
     if (!cue)
         return;
 
     // 4.8.10.12.5 Text track API
 
     // The removeCue(cue) method of TextTrack objects, when invoked, must run the following steps:
 
     // 1. If the given cue is not currently listed in the method's TextTrack
     // object's text track's text track list of cues, then throw a NotFoundError exception.
     if (cue->track() != this) {
         exceptionState.throwDOMException(NotFoundError, "The specified cue is not listed in the TextTrack's list of cues.");
         return;
     }
 
     // 2. Remove cue from the method's TextTrack object's text track's text track list of cues.
     if (!m_cues || !m_cues->remove(cue)) {
         exceptionState.throwDOMException(InvalidStateError, "Failed to remove the specified cue.");
         return;
     }
 
     cue->setTrack(0);
-    if (m_client)
-        m_client->textTrackRemoveCue(this, cue);
+    if (mediaElement())
+        mediaElement()->textTrackRemoveCue(this, cue);
 }
 
 VTTRegionList* TextTrack::ensureVTTRegionList()
 {
     if (!m_regions)
         m_regions = VTTRegionList::create();
 
     return m_regions.get();
 }
 
@@ skipping 55 matching lines @@
     if (!m_regions || !m_regions->remove(region)) {
         exceptionState.throwDOMException(InvalidStateError, "Failed to remove the specified region.");
         return;
     }
 
     region->setTrack(0);
 }
 
 void TextTrack::cueWillChange(TextTrackCue* cue)
 {
-    if (!m_client)
+    if (!mediaElement())
         return;
 
     // The cue may need to be repositioned in the media element's interval tree, may need to
     // be re-rendered, etc, so remove it before the modification...
-    m_client->textTrackRemoveCue(this, cue);
+    mediaElement()->textTrackRemoveCue(this, cue);
 }
 
 void TextTrack::cueDidChange(TextTrackCue* cue)
 {
-    if (!m_client)
+    if (!mediaElement())
         return;
 
     // Make sure the TextTrackCueList order is up-to-date.
     ensureTextTrackCueList()->updateCueIndex(cue);
 
     // ... and add it back again.
-    m_client->textTrackAddCue(this, cue);
+    mediaElement()->textTrackAddCue(this, cue);
 }
 
 int TextTrack::trackIndex()
 {
     ASSERT(m_trackList);
 
     if (m_trackIndex == invalidTrackIndex)
         m_trackIndex = m_trackList->getTrackIndex(this);
 
     return m_trackIndex;
@@ skipping 37 matching lines @@
 const AtomicString& TextTrack::interfaceName() const
 {
     return EventTargetNames::TextTrack;
 }
 
 ExecutionContext* TextTrack::executionContext() const
 {
     return m_document;
 }
 
+HTMLMediaElement* TextTrack::mediaElement()
+{
+    return m_trackList ? m_trackList->owner() : 0;
+}
+
 } // namespace WebCore