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

cc/test/animation_test_common.h

Index: cc/test/animation_test_common.h
diff --git a/cc/test/animation_test_common.h b/cc/test/animation_test_common.h
index a69f0c95f6e1df537bb82b2e0cd7a5d550ee7b1a..2c41518794a267e6e6aa7d0b47046850b2439cad 100644
--- a/cc/test/animation_test_common.h
+++ b/cc/test/animation_test_common.h
@@ -27,7 +27,7 @@ class FakeFloatAnimationCurve : public FloatAnimationCurve {
   ~FakeFloatAnimationCurve() override;
 
   base::TimeDelta Duration() const override;
-  float GetValue(double now) const override;
+  float GetValue(base::TimeDelta now) const override;
   scoped_ptr<AnimationCurve> Clone() const override;
 
  private:
@@ -40,7 +40,7 @@ class FakeTransformTransition : public TransformAnimationCurve {
   ~FakeTransformTransition() override;
 
   base::TimeDelta Duration() const override;
-  gfx::Transform GetValue(double time) const override;
+  gfx::Transform GetValue(base::TimeDelta time) const override;
   bool AnimatedBoundsForBox(const gfx::BoxF& box,
                             gfx::BoxF* bounds) const override;
   bool AffectsScale() const override;
@@ -60,7 +60,7 @@ class FakeFloatTransition : public FloatAnimationCurve {
   ~FakeFloatTransition() override;
 
   base::TimeDelta Duration() const override;
-  float GetValue(double time) const override;
+  float GetValue(base::TimeDelta time) const override;
 
   scoped_ptr<AnimationCurve> Clone() const override;