Animation start scale should be considered for the raster scale

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 b2909b8711fcf82da8238fc12bafed87bd00874f..6f4b6cbf390821104858aa256e8c86420ec35fcd 100644
--- a/cc/test/animation_test_common.h
+++ b/cc/test/animation_test_common.h
@@ -46,6 +46,8 @@ class FakeTransformTransition : public TransformAnimationCurve {
   bool AffectsScale() const override;
   bool IsTranslation() const override;
   bool PreservesAxisAlignment() const override;
+  bool AnimationStartScale(bool forward_direction,
+                           float* start_scale) const override;
   bool MaximumTargetScale(bool forward_direction,
                           float* max_scale) const override;