Make PropertyHandle instances const references where possible

third_party/WebKit/Source/core/animation/InvalidatableInterpolation.h

 // Copyright 2015 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.
 
 #ifndef InvalidatableInterpolation_h
 #define InvalidatableInterpolation_h
 
 #include "core/animation/Interpolation.h"
 #include "core/animation/InterpolationType.h"
 #include "core/animation/InterpolationTypesMap.h"
 #include "core/animation/PrimitiveInterpolation.h"
 #include "core/animation/TypedInterpolationValue.h"
 #include <memory>
 
 namespace blink {
 
 // TODO(alancutter): This class will replace *StyleInterpolation and
 // Interpolation. For now it needs to distinguish itself during the refactor and
 // temporarily has an ugly name.
 class CORE_EXPORT InvalidatableInterpolation : public Interpolation {
  public:
   static PassRefPtr<InvalidatableInterpolation> create(
-      PropertyHandle property,
+      const PropertyHandle& property,
       PassRefPtr<PropertySpecificKeyframe> startKeyframe,
       PassRefPtr<PropertySpecificKeyframe> endKeyframe) {
     return adoptRef(new InvalidatableInterpolation(
         property, std::move(startKeyframe), std::move(endKeyframe)));
   }
 
-  PropertyHandle getProperty() const final { return m_property; }
+  const PropertyHandle& getProperty() const final { return m_property; }
   virtual void interpolate(int iteration, double fraction);
   bool dependsOnUnderlyingValue() const final;
   static void applyStack(const ActiveInterpolations&,
                          InterpolationEnvironment&);
 
   virtual bool isInvalidatableInterpolation() const { return true; }
 
  private:
-  InvalidatableInterpolation(PropertyHandle property,
+  InvalidatableInterpolation(const PropertyHandle& property,
                              PassRefPtr<PropertySpecificKeyframe> startKeyframe,
                              PassRefPtr<PropertySpecificKeyframe> endKeyframe)
       : Interpolation(),
         m_property(property),
         m_interpolationTypes(nullptr),
         m_interpolationTypesVersion(0),
         m_startKeyframe(startKeyframe),
         m_endKeyframe(endKeyframe),
         m_currentFraction(std::numeric_limits<double>::quiet_NaN()),
         m_isConversionCached(false) {}
@@ skipping 36 matching lines @@
 
 DEFINE_TYPE_CASTS(InvalidatableInterpolation,
                   Interpolation,
                   value,
                   value->isInvalidatableInterpolation(),
                   value.isInvalidatableInterpolation());
 
 }  // namespace blink
 
 #endif  // InvalidatableInterpolation_h