Remove special cases for viewport units, and add tests for viewport units in calc().

Source/core/animation/AnimatableLength.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 72 matching lines @@
 {
     // Avoid creating a CSSValue in the common cases
     if (m_lengthUnitType == CSSPrimitiveValue::UnitTypePixels)
         return Length(clampedNumber(range) * conversionData.zoom(), Fixed);
     if (m_lengthUnitType == CSSPrimitiveValue::UnitTypePercentage)
         return Length(clampedNumber(range), Percent);
 
     return toCSSPrimitiveValue(range)->convertToLength<AnyConversion>(conversionData);
 }
 
-bool AnimatableLength::usesDefaultInterpolationWith(const AnimatableValue* value) const
-{
-    const AnimatableLength* length = toAnimatableLength(value);
-    CSSPrimitiveValue::LengthUnitType type = commonUnitType(length);
-    return isCalc(type) && (isViewportUnit() || length->isViewportUnit());
-}
-
 PassRefPtrWillBeRawPtr<AnimatableValue> AnimatableLength::interpolateTo(const AnimatableValue* value, double fraction) const
 {
     const AnimatableLength* length = toAnimatableLength(value);
     CSSPrimitiveValue::LengthUnitType type = commonUnitType(length);
     if (!isCalc(type))
         return AnimatableLength::create(blend(m_lengthValue, length->m_lengthValue, fraction), type);
-
-    // FIXME(crbug.com/168840): Support for viewport units in calc needs to be added before we can blend them with other units.
-    if (isViewportUnit() || length->isViewportUnit())
-        return defaultInterpolateTo(this, value, fraction);
-
     return AnimatableLength::create(scale(1 - fraction).get(), length->scale(fraction).get());
 }
 
 PassRefPtrWillBeRawPtr<AnimatableValue> AnimatableLength::addWith(const AnimatableValue* value) const
 {
     // Optimization for adding with 0.
     if (isUnitlessZero())
         return takeConstRef(value);
 
     const AnimatableLength* length = toAnimatableLength(value);
@@ skipping 56 matching lines @@
     return AnimatableLength::create(m_lengthValue * factor, m_lengthUnitType);
 }
 
 void AnimatableLength::trace(Visitor* visitor)
 {
     visitor->trace(m_calcExpression);
     visitor->trace(m_cachedCSSPrimitiveValue);
 }
 
 } // namespace WebCore