CC::Animations should use TimeTicks & TimeDelta to represent time

ui/compositor/layer_animator.cc

 // Copyright (c) 2012 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.
 
 #include "ui/compositor/layer_animator.h"
 
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "cc/animation/animation_id_provider.h"
@@ skipping 304 matching lines @@
     return;
   DCHECK(running->is_sequence_alive());
 
   if (running->sequence()->animation_group_id() != event.group_id)
     return;
 
   running->sequence()->OnThreadedAnimationStarted(event);
   if (!running->sequence()->waiting_for_group_start())
     return;
 
-  base::TimeTicks start_time = base::TimeTicks::FromInternalValue(
-      event.monotonic_time * base::Time::kMicrosecondsPerSecond);
+  base::TimeTicks start_time = event.monotonic_time;
 
   running->sequence()->set_waiting_for_group_start(false);
 
   // The call to GetRunningAnimation made above already purged deleted
   // animations, so we are guaranteed that all the animations we iterate
   // over now are alive.
   for (RunningAnimations::iterator iter = running_animations_.begin();
        iter != running_animations_.end(); ++iter) {
     // Ensure that each sequence is only Started once, regardless of the
     // number of sequences in the group that have threaded first elements.
@@ skipping 504 matching lines @@
 }
 
 LayerAnimator::RunningAnimation::RunningAnimation(
     const base::WeakPtr<LayerAnimationSequence>& sequence)
     : sequence_(sequence) {
 }
 
 LayerAnimator::RunningAnimation::~RunningAnimation() { }
 
 }  // namespace ui