Make RenderObject::style() return a const object

Source/core/animation/css/CSSAnimations.cpp

Index: Source/core/animation/css/CSSAnimations.cpp
diff --git a/Source/core/animation/css/CSSAnimations.cpp b/Source/core/animation/css/CSSAnimations.cpp
index 7ca241a49405e2f544fe2611b1400edd229aeb11..77c35076b6425eb32b712c21513f35eaceb01060 100644
--- a/Source/core/animation/css/CSSAnimations.cpp
+++ b/Source/core/animation/css/CSSAnimations.cpp
@@ -85,7 +85,7 @@ CSSPropertyID propertyForAnimation(CSSPropertyID property)
     return property;
 }
 
-static void resolveKeyframes(StyleResolver* resolver, const Element* animatingElement, Element& element, const LayoutStyle& style, LayoutStyle* parentStyle, const AtomicString& name, TimingFunction* defaultTimingFunction,
+static void resolveKeyframes(StyleResolver* resolver, const Element* animatingElement, Element& element, const LayoutStyle& style, const LayoutStyle* parentStyle, const AtomicString& name, TimingFunction* defaultTimingFunction,
     AnimatableValueKeyframeVector& keyframes)
 {
     // When the animating element is null, use its parent for scoping purposes.
@@ -225,7 +225,7 @@ bool CSSAnimations::isTransitionAnimationForInspector(const AnimationPlayer& pla
     return false;
 }
 
-PassOwnPtrWillBeRawPtr<CSSAnimationUpdate> CSSAnimations::calculateUpdate(const Element* animatingElement, Element& element, const LayoutStyle& style, LayoutStyle* parentStyle, StyleResolver* resolver)
+PassOwnPtrWillBeRawPtr<CSSAnimationUpdate> CSSAnimations::calculateUpdate(const Element* animatingElement, Element& element, const LayoutStyle& style, const LayoutStyle* parentStyle, StyleResolver* resolver)
 {
     OwnPtrWillBeRawPtr<CSSAnimationUpdate> update = adoptPtrWillBeNoop(new CSSAnimationUpdate());
     calculateAnimationUpdate(update.get(), animatingElement, element, style, parentStyle, resolver);
@@ -235,7 +235,7 @@ PassOwnPtrWillBeRawPtr<CSSAnimationUpdate> CSSAnimations::calculateUpdate(const
     return update->isEmpty() ? nullptr : update.release();
 }
 
-void CSSAnimations::calculateAnimationUpdate(CSSAnimationUpdate* update, const Element* animatingElement, Element& element, const LayoutStyle& style, LayoutStyle* parentStyle, StyleResolver* resolver)
+void CSSAnimations::calculateAnimationUpdate(CSSAnimationUpdate* update, const Element* animatingElement, Element& element, const LayoutStyle& style, const LayoutStyle* parentStyle, StyleResolver* resolver)
 {
     const ActiveAnimations* activeAnimations = animatingElement ? animatingElement->activeAnimations() : nullptr;