cc: Use HighResNow as timebase if it is fast and reliable

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"
+#include "cc/output/begin_frame_args.h"
 #include "ui/compositor/compositor.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/layer_animation_delegate.h"
 #include "ui/compositor/layer_animation_observer.h"
 #include "ui/compositor/layer_animation_sequence.h"
 #include "ui/gfx/animation/animation_container.h"
+#include "ui/gfx/frame_time.h"
 
 #define SAFE_INVOKE_VOID(function, running_anim, ...) \
     if (running_anim.is_sequence_alive()) \
       function(running_anim.sequence(), ##__VA_ARGS__)
 #define SAFE_INVOKE_BOOL(function, running_anim) \
     ((running_anim.is_sequence_alive()) \
         ? function(running_anim.sequence()) \
         : false)
 #define SAFE_INVOKE_PTR(function, running_anim) \
     ((running_anim.is_sequence_alive()) \
@@ skipping 143 matching lines @@
       StartAnimation(*iter);
     }
     return;
   }
 
   adding_animations_ = true;
   if (!is_animating()) {
     if (GetAnimationContainer()->is_running())
       last_step_time_ = GetAnimationContainer()->last_tick_time();
     else
-      last_step_time_ = base::TimeTicks::Now();
+      last_step_time_ = gfx::FrameTime::Now();

[ajuma, 2013/10/17 20:14:56]

We'll also need to make the same change in
test/layer_animator_test_controller.cc and in layer_animator_unittest.cc

   }
 
   // Collect all the affected properties.
   LayerAnimationElement::AnimatableProperties animated_properties;
   std::vector<LayerAnimationSequence*>::const_iterator iter;
   for (iter = animations.begin(); iter != animations.end(); ++iter) {
     animated_properties.insert((*iter)->properties().begin(),
                                (*iter)->properties().end());
   }
 
@@ skipping 570 matching lines @@
   // internally).
   // All LayerAnimators share the same AnimationContainer. Use the
   // last_tick_time() from there to ensure animations started during the same
   // event complete at the same time.
   base::TimeTicks start_time;
   if (is_animating() || adding_animations_)
     start_time = last_step_time_;
   else if (GetAnimationContainer()->is_running())
     start_time = GetAnimationContainer()->last_tick_time();
   else
-    start_time = base::TimeTicks::Now();
+    start_time = gfx::FrameTime::Now();
 
   if (!sequence->animation_group_id())
     sequence->set_animation_group_id(cc::AnimationIdProvider::NextGroupId());
   if (!sequence->waiting_for_group_start() ||
       sequence->IsFirstElementThreaded()) {
     sequence->set_start_time(start_time);
     sequence->Start(delegate());
   }
   running_animations_.push_back(
       RunningAnimation(sequence->AsWeakPtr()));
@@ skipping 62 matching lines @@
 }
 
 LayerAnimator::RunningAnimation::RunningAnimation(
     const base::WeakPtr<LayerAnimationSequence>& sequence)
     : sequence_(sequence) {
 }
 
 LayerAnimator::RunningAnimation::~RunningAnimation() { }
 
 }  // namespace ui