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

ui/compositor/layer_animation_sequence.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_animation_sequence.h"
 
 #include <algorithm>
 #include <iterator>
 
 #include "base/debug/trace_event.h"
@@ skipping 201 matching lines @@
     const cc::AnimationEvent& event) {
   if (elements_.empty() || event.group_id != animation_group_id_)
     return;
 
   size_t current_index = last_element_ % elements_.size();
   LayerAnimationElement::AnimatableProperties element_properties =
     elements_[current_index]->properties();
   LayerAnimationElement::AnimatableProperty event_property =
       LayerAnimationElement::ToAnimatableProperty(event.target_property);
   DCHECK(element_properties & event_property);
-  elements_[current_index]->set_effective_start_time(
-      base::TimeTicks::FromInternalValue(
-          event.monotonic_time * base::Time::kMicrosecondsPerSecond));
+  elements_[current_index]->set_effective_start_time(event.monotonic_time);
 }
 
 void LayerAnimationSequence::OnScheduled() {
   NotifyScheduled();
 }
 
 void LayerAnimationSequence::OnAnimatorDestroyed() {
   if (observers_.might_have_observers()) {
     ObserverListBase<LayerAnimationObserver>::Iterator it(observers_);
     LayerAnimationObserver* obs;
@@ skipping 39 matching lines @@
 
 LayerAnimationElement* LayerAnimationSequence::CurrentElement() const {
   if (elements_.empty())
     return NULL;
 
   size_t current_index = last_element_ % elements_.size();
   return elements_[current_index].get();
 }
 
 }  // namespace ui