ThumbThicknessScaleAtAnimationProgress   75 cc/animation/scrollbar_animation_controller_thinning.cc   float thumb_thickness_scale = ThumbThicknessScaleAtAnimationProgress(
ThumbThicknessScaleAtAnimationProgress   63 cc/animation/scrollbar_animation_controller_thinning.h   float ThumbThicknessScaleAtAnimationProgress(float progress);