Simplify and test SVGInterpolation effect application

third_party/WebKit/Source/core/animation/SVGInterpolation.cpp

-// 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.
-
-#include "config.h"
-#include "core/animation/SVGInterpolation.h"
-
-#include "core/svg/SVGAnimateElement.h" // findElementInstances
-
-namespace blink {
-
-void SVGInterpolation::apply(SVGElement& targetElement) const
-{
-    SVGElement::InstanceUpdateBlocker blocker(&targetElement);
-    RefPtrWillBeRawPtr<SVGPropertyBase> value = interpolatedValue(targetElement);
-    SVGElementInstances instances = SVGAnimateElement::findElementInstances(&targetElement);
-
-    for (SVGElement* element : instances) {
-        RefPtrWillBeRawPtr<SVGAnimatedPropertyBase> animatedProperty =
-            element->propertyFromAttribute(attributeName());
-        if (animatedProperty) {
-            animatedProperty->setAnimatedValue(value);
-            element->invalidateSVGAttributes();
-            element->svgAttributeChanged(attributeName());
-        }
-    }
-}
-
-}