AnimationTimeline::serviceAnimations should reserveInitialCapacity

Source/core/animation/AnimationTimeline.cpp

 /*
  * Copyright (C) 2013 Google 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.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 82 matching lines @@
     m_timing->serviceOnNextFrame();
 }
 
 void AnimationTimeline::serviceAnimations(TimingUpdateReason reason)
 {
     TRACE_EVENT0("blink", "AnimationTimeline::serviceAnimations");
 
     m_timing->cancelWake();
 
     double timeToNextEffect = std::numeric_limits<double>::infinity();
+
     WillBeHeapVector<RawPtrWillBeMember<AnimationPlayer> > players;
+    players.reserveInitialCapacity(m_playersNeedingUpdate.size());
     for (WillBeHeapHashSet<RefPtrWillBeMember<AnimationPlayer> >::iterator it = m_playersNeedingUpdate.begin(); it != m_playersNeedingUpdate.end(); ++it)
         players.append(it->get());
 
     std::sort(players.begin(), players.end(), AnimationPlayer::hasLowerPriority);
 
     for (size_t i = 0; i < players.size(); ++i) {
         AnimationPlayer* player = players[i];
         if (player->update(reason))
             timeToNextEffect = std::min(timeToNextEffect, player->timeToEffectChange());
         else
@@ skipping 110 matching lines @@
 
 void AnimationTimeline::trace(Visitor* visitor)
 {
     visitor->trace(m_document);
     visitor->trace(m_timing);
     visitor->trace(m_playersNeedingUpdate);
     visitor->trace(m_players);
 }
 
 } // namespace