Push cue timeline management out of LoadableTextTrack

Source/core/html/track/TextTrack.cpp

Index: Source/core/html/track/TextTrack.cpp
diff --git a/Source/core/html/track/TextTrack.cpp b/Source/core/html/track/TextTrack.cpp
index 54f2cbdec176b2a2c6a4aefe59f6fb5adc5abd34..b96e6e5c6704727cba8d4cd690828d9895f4738b 100644
--- a/Source/core/html/track/TextTrack.cpp
+++ b/Source/core/html/track/TextTrack.cpp
@@ -210,6 +210,19 @@ void TextTrack::removeAllCues()
     m_cues = nullptr;
 }
 
+void TextTrack::addListOfCues(WillBeHeapVector<RefPtrWillBeMember<TextTrackCue>>& listOfNewCues)
+{
+    TextTrackCueList* cues = ensureTextTrackCueList();
+
+    for (auto& newCue : listOfNewCues) {
+        newCue->setTrack(this);
+        cues->add(newCue.release());
+    }
+
+    if (cueTimeline() && mode() != disabledKeyword())
+        cueTimeline()->addCues(this, cues);
+}
+
 TextTrackCueList* TextTrack::activeCues() const
 {
     // 4.8.10.12.5 If the text track mode ... is not the text track disabled mode,