NOT FOR REVIEW - convert to cc animation

chrome/browser/android/vr_shell/easing.cc

-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "chrome/browser/android/vr_shell/easing.h"
-
-#include <cmath>
-
-#include "base/logging.h"
-
-namespace vr_shell {
-namespace easing {
-
-double Easing::CalculateValue(double input) {
-  DCHECK(input >= 0.0 && input <= 1.0);
-  return CalculateValueImpl(input);
-}
-
-CubicBezier::CubicBezier(double p1x, double p1y, double p2x, double p2y)
-    : bezier_(p1x, p1y, p2x, p2y) {}
-
-double CubicBezier::CalculateValueImpl(double state) {
-  return bezier_.Solve(state);
-}
-
-EaseIn::EaseIn(double power) : power_(power) {}
-double EaseIn::CalculateValueImpl(double state) {
-  return pow(state, power_);
-}
-
-EaseOut::EaseOut(double power) : power_(power) {}
-double EaseOut::CalculateValueImpl(double state) {
-  return 1.0 - pow(1.0 - state, power_);
-}
-
-EaseInOut::EaseInOut(double power) : ease_in_(power) {}
-double EaseInOut::CalculateValueImpl(double state) {
-  if (state < 0.5) {
-    return ease_in_.CalculateValueImpl(state * 2) / 2;
-  } else {
-    return 1.0 - ease_in_.CalculateValueImpl((1.0 - state) * 2) / 2;
-  }
-}
-
-double Linear::CalculateValueImpl(double state) {
-  return state;
-}
-
-}  // namespace easing
-}  // namespace vr_shell