CC Animation: Erase EaseTimingFunction helpers.

cc/animation/scroll_offset_animation_curve.cc

 // Copyright 2013 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 "cc/animation/scroll_offset_animation_curve.h"
 
 #include <algorithm>
 #include <cmath>
 
 #include "base/logging.h"
@@ skipping 51 matching lines @@
   }
   return base::TimeDelta::FromMicroseconds(duration / kDurationDivisor *
                                            base::Time::kMicrosecondsPerSecond);
 }
 
 static std::unique_ptr<TimingFunction> EaseOutWithInitialVelocity(
     double velocity) {
   // Clamp velocity to a sane value.
   velocity = std::min(std::max(velocity, -1000.0), 1000.0);
 
-  // Based on EaseInOutTimingFunction::Create with first control point scaled.
+  // Based on CubicBezierTimingFunction::EaseType::EASE_IN_OUT preset
+  // with first control point scaled.
   const double x1 = 0.42;
   const double y1 = velocity * x1;
   return CubicBezierTimingFunction::Create(x1, y1, 0.58, 1);
 }
 
 }  // namespace
 
 std::unique_ptr<ScrollOffsetAnimationCurve> ScrollOffsetAnimationCurve::Create(
     const gfx::ScrollOffset& target_value,
     std::unique_ptr<TimingFunction> timing_function,
@@ skipping 143 matching lines @@
       (MaximumDimension(old_delta) / MaximumDimension(new_delta));
 
   initial_value_ = current_position;
   target_value_ = new_target;
   total_animation_duration_ = base::TimeDelta::FromSecondsD(t + new_duration);
   last_retarget_ = base::TimeDelta::FromSecondsD(t);
   timing_function_ = EaseOutWithInitialVelocity(new_normalized_velocity);
 }
 
 }  // namespace cc