Animation: Remove ASSERT_NOT_REACHED from LengthStyleInterpolation

Source/core/animation/InterpolableValue.cpp

 // Copyright 2014 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 "config.h"
 #include "core/animation/InterpolableValue.h"
 
 namespace blink {
 
 DEFINE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(InterpolableValue);
 
 void InterpolableNumber::interpolate(const InterpolableValue &to, const double progress, InterpolableValue& result) const
 {
     const InterpolableNumber& toNumber = toInterpolableNumber(to);
     InterpolableNumber& resultNumber = toInterpolableNumber(result);
 
     if (progress == 0)
         resultNumber.m_value = m_value;
     else if (progress == 1)
         resultNumber.m_value = toNumber.m_value;
     else
-        resultNumber.m_value = m_value * (1 - progress) + toNumber.m_value * progress;
+        resultNumber.m_value = m_value + (toNumber.m_value - m_value) * progress;

[shans, 2015/01/07 23:07:49]

Don't do this - you'll cause interpolation from large negative values to large
positive values to produce incorrect results.

[evemj (not active), 2015/01/07 23:28:03]

Done.

 }
 
 void InterpolableBool::interpolate(const InterpolableValue &to, const double progress, InterpolableValue& result) const
 {
     const InterpolableBool& toBool = toInterpolableBool(to);
     InterpolableBool& resultBool = toInterpolableBool(result);
 
     if (progress < 0.5)
         resultBool.m_value = m_value;
     else
@@ skipping 84 matching lines @@
     resultValue.m_value = AnimatableValue::interpolate(m_value.get(), toValue.m_value.get(), progress);
 }
 
 void InterpolableAnimatableValue::trace(Visitor* visitor)
 {
     visitor->trace(m_value);
     InterpolableValue::trace(visitor);
 }
 
 }