gfx: Add FrameTime and DisplayTime classes

ui/gfx/animation/linear_animation.h

Index: ui/gfx/animation/linear_animation.h
diff --git a/ui/gfx/animation/linear_animation.h b/ui/gfx/animation/linear_animation.h
index 401f1be18bbac8c1f1c2c863c43efef282d8e63a..4d9d2a1d697f62657d71bf43758cfa3cb27dc7a7 100644
--- a/ui/gfx/animation/linear_animation.h
+++ b/ui/gfx/animation/linear_animation.h
@@ -50,7 +50,7 @@ class GFX_EXPORT LinearAnimation : public Animation {
   // Invoked by the AnimationContainer when the animation is running to advance
   // the animation. Use |time_now| rather than Time::Now to avoid multiple
   // animations running at the same time diverging.
-  virtual void Step(base::TimeTicks time_now) OVERRIDE;
+  virtual void Step(gfx::FrameTime time_now) OVERRIDE;
 
   // Overriden to initialize state.
   virtual void AnimationStarted() OVERRIDE;