CSSValue Immediates: Replace CSSValue usage with const references

Source/core/css/resolver/StyleResolver.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
@@ skipping 621 matching lines @@
 
     if (state.style()->hasViewportUnits())
         document().setHasViewportUnits();
 
     // Now return the style.
     return state.takeStyle();
 }
 
 // This function is used by the WebAnimations JavaScript API method animate().
 // FIXME: Remove this when animate() switches away from resolution-dependent parsing.
-PassRefPtrWillBeRawPtr<AnimatableValue> StyleResolver::createAnimatableValueSnapshot(Element& element, const ComputedStyle* baseStyle, CSSPropertyID property, NullableCSSValue value)
+PassRefPtrWillBeRawPtr<AnimatableValue> StyleResolver::createAnimatableValueSnapshot(Element& element, const ComputedStyle* baseStyle, CSSPropertyID property, const NullableCSSValue& value)
 {
     StyleResolverState state(element.document(), &element);
     state.setStyle(baseStyle ? ComputedStyle::clone(*baseStyle) : ComputedStyle::create());
     return createAnimatableValueSnapshot(state, property, value);
 }
 
-PassRefPtrWillBeRawPtr<AnimatableValue> StyleResolver::createAnimatableValueSnapshot(StyleResolverState& state, CSSPropertyID property, NullableCSSValue value)
+PassRefPtrWillBeRawPtr<AnimatableValue> StyleResolver::createAnimatableValueSnapshot(StyleResolverState& state, CSSPropertyID property, const NullableCSSValue& value)
 {
     if (value) {
         StyleBuilder::applyProperty(property, state, *value);
         state.fontBuilder().createFont(state.document().styleEngine().fontSelector(), state.mutableStyleRef());
     }
     return CSSAnimatableValueFactory::create(property, *state.style());
 }
 
 PassRefPtrWillBeRawPtr<PseudoElement> StyleResolver::createPseudoElement(Element* parent, PseudoId pseudoId)
 {
@@ skipping 774 matching lines @@
     visitor->trace(m_watchedSelectorsRules);
     visitor->trace(m_treeBoundaryCrossingRules);
     visitor->trace(m_styleResourceLoader);
     visitor->trace(m_styleSharingLists);
     visitor->trace(m_pendingStyleSheets);
     visitor->trace(m_document);
 #endif
 }
 
 } // namespace blink