Make classes and structures in core/html fast-allocated.

Source/core/html/track/CueTimeline.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CueTimeline_h
 #define CueTimeline_h
 
 #include "core/html/track/TextTrackCue.h"
 #include "core/html/track/vtt/VTTCue.h"
 #include "platform/PODIntervalTree.h"
@@ skipping 10 matching lines @@
 // reason) so we leave it as a raw pointer at the moment. This is safe
 // because CueTimeline and TextTrackCue are guaranteed to die at the same time
 // when the owner HTMLMediaElement dies. Thus the raw TextTrackCue* cannot
 // become stale pointers.
 typedef PODIntervalTree<double, TextTrackCue*> CueIntervalTree;
 typedef CueIntervalTree::IntervalType CueInterval;
 typedef Vector<CueInterval> CueList;
 
 // This class manages the timeline and rendering updates of cues associated
 // with TextTracks. Owned by a HTMLMediaElement.
-class CueTimeline : public NoBaseWillBeGarbageCollectedFinalized<CueTimeline> {
+class CueTimeline final : public NoBaseWillBeGarbageCollectedFinalized<CueTimeline> {
+    WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED(CueTimeline);
 public:
     CueTimeline(HTMLMediaElement&);
 
     void addCues(TextTrack*, const TextTrackCueList*);
     void addCue(TextTrack*, PassRefPtrWillBeRawPtr<TextTrackCue>);
     void removeCues(TextTrack*, const TextTrackCueList*);
     void removeCue(TextTrack*, PassRefPtrWillBeRawPtr<TextTrackCue>);
 
     void hideCues(TextTrack*, const TextTrackCueList*);
 
@@ skipping 56 matching lines @@
     static String string(TextTrackCue* const& cue)
     {
         return cue->toString();
     }
 };
 #endif
 
 } // namespace blink
 
 #endif // CueTimeline_h