Make Keyframe use TimeTicks/TimeDelta to represent time instead of double.

ui/compositor/float_animation_curve_adapter.cc

Index: ui/compositor/float_animation_curve_adapter.cc
diff --git a/ui/compositor/float_animation_curve_adapter.cc b/ui/compositor/float_animation_curve_adapter.cc
index 3b5e155e3a154e2cf3910977bb58058352cfcb97..d40d70188014106df98f39b3f09a56d37b633885 100644
--- a/ui/compositor/float_animation_curve_adapter.cc
+++ b/ui/compositor/float_animation_curve_adapter.cc
@@ -4,6 +4,8 @@
 
 #include "ui/compositor/float_animation_curve_adapter.h"
 
+#include "cc/base/time_util.h"
+
 namespace ui {
 
 FloatAnimationCurveAdapter::FloatAnimationCurveAdapter(
@@ -26,12 +28,12 @@ scoped_ptr<cc::AnimationCurve> FloatAnimationCurveAdapter::Clone() const {
       tween_type_, initial_value_, target_value_, duration_));
 }
 
-float FloatAnimationCurveAdapter::GetValue(double t) const {
-  if (t >= duration_.InSecondsF())
+float FloatAnimationCurveAdapter::GetValue(base::TimeDelta t) const {
+  if (t >= duration_)
     return target_value_;
-  if (t <= 0.0)
+  if (t <= base::TimeDelta())
     return initial_value_;
-  double progress = t / duration_.InSecondsF();
+  double progress = cc::TimeUtil::Divide(t, duration_);
   return gfx::Tween::FloatValueBetween(
       gfx::Tween::CalculateValue(tween_type_, progress),
       initial_value_,