Source/core/css/PropertySetCSSStyleDeclaration.cpp - platform/external/chromium_org/third_party/WebKit - Git at Google

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Research In Motion Limited. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */

 #include "config.h"
 #include "core/css/PropertySetCSSStyleDeclaration.h"

 #include "HTMLNames.h"
 #include "RuntimeEnabledFeatures.h"
 #include "bindings/v8/ExceptionState.h"
 #include "core/css/CSSParser.h"
 #include "core/css/CSSStyleSheet.h"
 #include "core/css/StylePropertySet.h"
 #include "core/dom/Element.h"
 #include "core/dom/MutationObserverInterestGroup.h"
 #include "core/dom/MutationRecord.h"
 #include "core/inspector/InspectorInstrumentation.h"

 using namespace std;

 namespace WebCore {

 namespace {

 class StyleAttributeMutationScope {
     WTF_MAKE_NONCOPYABLE(StyleAttributeMutationScope);
 public:
     StyleAttributeMutationScope(PropertySetCSSStyleDeclaration* decl)
     {
         ++s_scopeCount;

         if (s_scopeCount != 1) {
             ASSERT(s_currentDecl == decl);
             return;
         }

         ASSERT(!s_currentDecl);
         s_currentDecl = decl;

         if (!s_currentDecl->parentElement())
             return;

         bool shouldReadOldValue = false;

         m_mutationRecipients = MutationObserverInterestGroup::createForAttributesMutation(*s_currentDecl->parentElement(), HTMLNames::styleAttr);
         if (m_mutationRecipients && m_mutationRecipients->isOldValueRequested())
             shouldReadOldValue = true;

         AtomicString oldValue;
         if (shouldReadOldValue)
             oldValue = s_currentDecl->parentElement()->getAttribute(HTMLNames::styleAttr);

         if (m_mutationRecipients) {
             AtomicString requestedOldValue = m_mutationRecipients->isOldValueRequested() ? oldValue : nullAtom;
             m_mutation = MutationRecord::createAttributes(s_currentDecl->parentElement(), HTMLNames::styleAttr, requestedOldValue);
         }
     }

     ~StyleAttributeMutationScope()
     {
         --s_scopeCount;
         if (s_scopeCount)
             return;

         if (m_mutation && s_shouldDeliver)
             m_mutationRecipients->enqueueMutationRecord(m_mutation);

         s_shouldDeliver = false;
         if (!s_shouldNotifyInspector) {
             s_currentDecl = 0;
             return;
         }
         // We have to clear internal state before calling Inspector's code.
         PropertySetCSSStyleDeclaration* localCopyStyleDecl = s_currentDecl;
         s_currentDecl = 0;
         s_shouldNotifyInspector = false;
         if (localCopyStyleDecl->parentElement())
             InspectorInstrumentation::didInvalidateStyleAttr(localCopyStyleDecl->parentElement());
     }

     void enqueueMutationRecord()
     {
         s_shouldDeliver = true;
     }

     void didInvalidateStyleAttr()
     {
         s_shouldNotifyInspector = true;
     }

 private:
     static unsigned s_scopeCount;
     static PropertySetCSSStyleDeclaration* s_currentDecl;
     static bool s_shouldNotifyInspector;
     static bool s_shouldDeliver;

     OwnPtr<MutationObserverInterestGroup> m_mutationRecipients;
     RefPtr<MutationRecord> m_mutation;
 };

 unsigned StyleAttributeMutationScope::s_scopeCount = 0;
 PropertySetCSSStyleDeclaration* StyleAttributeMutationScope::s_currentDecl = 0;
 bool StyleAttributeMutationScope::s_shouldNotifyInspector = false;
 bool StyleAttributeMutationScope::s_shouldDeliver = false;

 } // namespace

 void PropertySetCSSStyleDeclaration::ref()
 {
     m_propertySet->ref();
 }

 void PropertySetCSSStyleDeclaration::deref()
 {
     m_propertySet->deref();
 }

 unsigned PropertySetCSSStyleDeclaration::length() const
 {
     return m_propertySet->propertyCount();
 }

 String PropertySetCSSStyleDeclaration::item(unsigned i) const
 {
     if (i >= m_propertySet->propertyCount())
         return "";
     return m_propertySet->propertyAt(i).cssName();
 }

 String PropertySetCSSStyleDeclaration::cssText() const
 {
     return m_propertySet->asText();
 }

 void PropertySetCSSStyleDeclaration::setCSSText(const String& text, ExceptionState& es)
 {
     StyleAttributeMutationScope mutationScope(this);
     willMutate();

     // FIXME: Detect syntax errors and set es.
     m_propertySet->parseDeclaration(text, contextStyleSheet());

     didMutate(PropertyChanged);

     mutationScope.enqueueMutationRecord();
 }

 PassRefPtr<CSSValue> PropertySetCSSStyleDeclaration::getPropertyCSSValue(const String& propertyName)
 {
     CSSPropertyID propertyID = cssPropertyID(propertyName);
     if (!propertyID)
         return 0;
     return cloneAndCacheForCSSOM(m_propertySet->getPropertyCSSValue(propertyID).get());
 }

 String PropertySetCSSStyleDeclaration::getPropertyValue(const String &propertyName)
 {
     CSSPropertyID propertyID = cssPropertyID(propertyName);
     if (!propertyID)
         return String();
     return m_propertySet->getPropertyValue(propertyID);
 }

 String PropertySetCSSStyleDeclaration::getPropertyPriority(const String& propertyName)
 {
     CSSPropertyID propertyID = cssPropertyID(propertyName);
     if (!propertyID)
         return String();
     return m_propertySet->propertyIsImportant(propertyID) ? "important" : "";
 }

 String PropertySetCSSStyleDeclaration::getPropertyShorthand(const String& propertyName)
 {
     CSSPropertyID propertyID = cssPropertyID(propertyName);
     if (!propertyID)
         return String();
     CSSPropertyID shorthandID = m_propertySet->getPropertyShorthand(propertyID);
     if (!shorthandID)
         return String();
     return getPropertyNameString(shorthandID);
 }

 bool PropertySetCSSStyleDeclaration::isPropertyImplicit(const String& propertyName)
 {
     CSSPropertyID propertyID = cssPropertyID(propertyName);
     if (!propertyID)
         return false;
     return m_propertySet->isPropertyImplicit(propertyID);
 }

 void PropertySetCSSStyleDeclaration::setProperty(const String& propertyName, const String& value, const String& priority, ExceptionState& es)
 {
     StyleAttributeMutationScope mutationScope(this);
     CSSPropertyID propertyID = cssPropertyID(propertyName);
     if (!propertyID)
         return;

     bool important = priority.find("important", 0, false) != kNotFound;

     willMutate();

     bool changed = m_propertySet->setProperty(propertyID, value, important, contextStyleSheet());

     didMutate(changed ? PropertyChanged : NoChanges);

     if (changed) {
         // CSS DOM requires raising SyntaxError of parsing failed, but this is too dangerous for compatibility,
         // see <http://bugs.webkit.org/show_bug.cgi?id=7296>.
         mutationScope.enqueueMutationRecord();
     }
 }

 String PropertySetCSSStyleDeclaration::removeProperty(const String& propertyName, ExceptionState& es)
 {
     StyleAttributeMutationScope mutationScope(this);
     CSSPropertyID propertyID = cssPropertyID(propertyName);
     if (!propertyID)
         return String();

     willMutate();

     String result;
     bool changed = m_propertySet->removeProperty(propertyID, &result);

     didMutate(changed ? PropertyChanged : NoChanges);

     if (changed)
         mutationScope.enqueueMutationRecord();
     return result;
 }

 PassRefPtr<CSSValue> PropertySetCSSStyleDeclaration::getPropertyCSSValueInternal(CSSPropertyID propertyID)
 {
     return m_propertySet->getPropertyCSSValue(propertyID);
 }

 String PropertySetCSSStyleDeclaration::getPropertyValueInternal(CSSPropertyID propertyID)
 {
     return m_propertySet->getPropertyValue(propertyID);
 }

 void PropertySetCSSStyleDeclaration::setPropertyInternal(CSSPropertyID propertyID, const String& value, bool important, ExceptionState& es)
 {
     StyleAttributeMutationScope mutationScope(this);
     willMutate();

     bool changed = m_propertySet->setProperty(propertyID, value, important, contextStyleSheet());

     didMutate(changed ? PropertyChanged : NoChanges);

     if (changed)
         mutationScope.enqueueMutationRecord();
 }

 unsigned PropertySetCSSStyleDeclaration::variableCount() const
 {
     ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
     return m_propertySet->variableCount();
 }

 String PropertySetCSSStyleDeclaration::variableValue(const AtomicString& name) const
 {
     ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
     return m_propertySet->variableValue(name);
 }

 bool PropertySetCSSStyleDeclaration::setVariableValue(const AtomicString& name, const String& value, ExceptionState&)
 {
     ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
     StyleAttributeMutationScope mutationScope(this);
     willMutate();
     bool changed = m_propertySet->setVariableValue(name, value);
     didMutate(changed ? PropertyChanged : NoChanges);
     if (changed)
         mutationScope.enqueueMutationRecord();
     return changed;
 }

 bool PropertySetCSSStyleDeclaration::removeVariable(const AtomicString& name)
 {
     ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
     StyleAttributeMutationScope mutationScope(this);
     willMutate();
     bool changed = m_propertySet->removeVariable(name);
     didMutate(changed ? PropertyChanged : NoChanges);
     if (changed)
         mutationScope.enqueueMutationRecord();
     return changed;
 }

 bool PropertySetCSSStyleDeclaration::clearVariables(ExceptionState&)
 {
     ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
     StyleAttributeMutationScope mutationScope(this);
     willMutate();
     bool changed = m_propertySet->clearVariables();
     didMutate(changed ? PropertyChanged : NoChanges);
     if (changed)
         mutationScope.enqueueMutationRecord();
     return changed;
 }

 PassRefPtr<CSSVariablesIterator> PropertySetCSSStyleDeclaration::variablesIterator() const
 {
     return m_propertySet->variablesIterator();
 }

 CSSValue* PropertySetCSSStyleDeclaration::cloneAndCacheForCSSOM(CSSValue* internalValue)
 {
     if (!internalValue)
         return 0;

     // The map is here to maintain the object identity of the CSSValues over multiple invocations.
     // FIXME: It is likely that the identity is not important for web compatibility and this code should be removed.
     if (!m_cssomCSSValueClones)
         m_cssomCSSValueClones = adoptPtr(new HashMap<CSSValue*, RefPtr<CSSValue> >);

     RefPtr<CSSValue>& clonedValue = m_cssomCSSValueClones->add(internalValue, RefPtr<CSSValue>()).iterator->value;
     if (!clonedValue)
         clonedValue = internalValue->cloneForCSSOM();
     return clonedValue.get();
 }

 StyleSheetContents* PropertySetCSSStyleDeclaration::contextStyleSheet() const
 {
     CSSStyleSheet* cssStyleSheet = parentStyleSheet();
     return cssStyleSheet ? cssStyleSheet->contents() : 0;
 }

 PassRefPtr<MutableStylePropertySet> PropertySetCSSStyleDeclaration::copyProperties() const
 {
     return m_propertySet->mutableCopy();
 }

 bool PropertySetCSSStyleDeclaration::cssPropertyMatches(CSSPropertyID propertyID, const CSSValue* propertyValue) const
 {
     return m_propertySet->propertyMatches(propertyID, propertyValue);
 }

 StyleRuleCSSStyleDeclaration::StyleRuleCSSStyleDeclaration(MutableStylePropertySet* propertySet, CSSRule* parentRule)
     : PropertySetCSSStyleDeclaration(propertySet)
     , m_refCount(1)
     , m_parentRule(parentRule)
 {
     m_propertySet->ref();
 }

 StyleRuleCSSStyleDeclaration::~StyleRuleCSSStyleDeclaration()
 {
     m_propertySet->deref();
 }

 void StyleRuleCSSStyleDeclaration::ref()
 {
     ++m_refCount;
 }

 void StyleRuleCSSStyleDeclaration::deref()
 {
     ASSERT(m_refCount);
     if (!--m_refCount)
         delete this;
 }

 void StyleRuleCSSStyleDeclaration::willMutate()
 {
     if (m_parentRule && m_parentRule->parentStyleSheet())
         m_parentRule->parentStyleSheet()->willMutateRules();
 }

 void StyleRuleCSSStyleDeclaration::didMutate(MutationType type)
 {
     if (type == PropertyChanged)
         m_cssomCSSValueClones.clear();

     // Style sheet mutation needs to be signaled even if the change failed. willMutateRules/didMutateRules must pair.
     if (m_parentRule && m_parentRule->parentStyleSheet())
         m_parentRule->parentStyleSheet()->didMutateRules();
 }

 CSSStyleSheet* StyleRuleCSSStyleDeclaration::parentStyleSheet() const
 {
     return m_parentRule ? m_parentRule->parentStyleSheet() : 0;
 }

 void StyleRuleCSSStyleDeclaration::reattach(MutableStylePropertySet* propertySet)
 {
     ASSERT(propertySet);
     m_propertySet->deref();
     m_propertySet = propertySet;
     m_propertySet->ref();
 }

 void InlineCSSStyleDeclaration::didMutate(MutationType type)
 {
     if (type == NoChanges)
         return;

     m_cssomCSSValueClones.clear();

     if (!m_parentElement)
         return;

     m_parentElement->setNeedsStyleRecalc(LocalStyleChange);
     m_parentElement->invalidateStyleAttribute();
     StyleAttributeMutationScope(this).didInvalidateStyleAttr();
 }

 CSSStyleSheet* InlineCSSStyleDeclaration::parentStyleSheet() const
 {
     return m_parentElement ? m_parentElement->document().elementSheet() : 0;
 }

 } // namespace WebCore
	/*
	* (C) 1999-2003 Lars Knoll (knoll@kde.org)
	* Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
	* Copyright (C) 2011 Research In Motion Limited. All rights reserved.
	*
	* This library is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Library General Public
	* License as published by the Free Software Foundation; either
	* version 2 of the License, or (at your option) any later version.
	*
	* This library is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Library General Public License for more details.
	*
	* You should have received a copy of the GNU Library General Public License
	* along with this library; see the file COPYING.LIB. If not, write to
	* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
	* Boston, MA 02110-1301, USA.
	*/

	#include "config.h"
	#include "core/css/PropertySetCSSStyleDeclaration.h"

	#include "HTMLNames.h"
	#include "RuntimeEnabledFeatures.h"
	#include "bindings/v8/ExceptionState.h"
	#include "core/css/CSSParser.h"
	#include "core/css/CSSStyleSheet.h"
	#include "core/css/StylePropertySet.h"
	#include "core/dom/Element.h"
	#include "core/dom/MutationObserverInterestGroup.h"
	#include "core/dom/MutationRecord.h"
	#include "core/inspector/InspectorInstrumentation.h"

	using namespace std;

	namespace WebCore {

	namespace {

	class StyleAttributeMutationScope {
	WTF_MAKE_NONCOPYABLE(StyleAttributeMutationScope);
	public:
	StyleAttributeMutationScope(PropertySetCSSStyleDeclaration* decl)
	{
	++s_scopeCount;

	if (s_scopeCount != 1) {
	ASSERT(s_currentDecl == decl);
	return;
	}

	ASSERT(!s_currentDecl);
	s_currentDecl = decl;

	if (!s_currentDecl->parentElement())
	return;

	bool shouldReadOldValue = false;

	m_mutationRecipients = MutationObserverInterestGroup::createForAttributesMutation(*s_currentDecl->parentElement(), HTMLNames::styleAttr);
	if (m_mutationRecipients && m_mutationRecipients->isOldValueRequested())
	shouldReadOldValue = true;

	AtomicString oldValue;
	if (shouldReadOldValue)
	oldValue = s_currentDecl->parentElement()->getAttribute(HTMLNames::styleAttr);

	if (m_mutationRecipients) {
	AtomicString requestedOldValue = m_mutationRecipients->isOldValueRequested() ? oldValue : nullAtom;
	m_mutation = MutationRecord::createAttributes(s_currentDecl->parentElement(), HTMLNames::styleAttr, requestedOldValue);
	}
	}

	~StyleAttributeMutationScope()
	{
	--s_scopeCount;
	if (s_scopeCount)
	return;

	if (m_mutation && s_shouldDeliver)
	m_mutationRecipients->enqueueMutationRecord(m_mutation);

	s_shouldDeliver = false;
	if (!s_shouldNotifyInspector) {
	s_currentDecl = 0;
	return;
	}
	// We have to clear internal state before calling Inspector's code.
	PropertySetCSSStyleDeclaration* localCopyStyleDecl = s_currentDecl;
	s_currentDecl = 0;
	s_shouldNotifyInspector = false;
	if (localCopyStyleDecl->parentElement())
	InspectorInstrumentation::didInvalidateStyleAttr(localCopyStyleDecl->parentElement());
	}

	void enqueueMutationRecord()
	{
	s_shouldDeliver = true;
	}

	void didInvalidateStyleAttr()
	{
	s_shouldNotifyInspector = true;
	}

	private:
	static unsigned s_scopeCount;
	static PropertySetCSSStyleDeclaration* s_currentDecl;
	static bool s_shouldNotifyInspector;
	static bool s_shouldDeliver;

	OwnPtr<MutationObserverInterestGroup> m_mutationRecipients;
	RefPtr<MutationRecord> m_mutation;
	};

	unsigned StyleAttributeMutationScope::s_scopeCount = 0;
	PropertySetCSSStyleDeclaration* StyleAttributeMutationScope::s_currentDecl = 0;
	bool StyleAttributeMutationScope::s_shouldNotifyInspector = false;
	bool StyleAttributeMutationScope::s_shouldDeliver = false;

	} // namespace

	void PropertySetCSSStyleDeclaration::ref()
	{
	m_propertySet->ref();
	}

	void PropertySetCSSStyleDeclaration::deref()
	{
	m_propertySet->deref();
	}

	unsigned PropertySetCSSStyleDeclaration::length() const
	{
	return m_propertySet->propertyCount();
	}

	String PropertySetCSSStyleDeclaration::item(unsigned i) const
	{
	if (i >= m_propertySet->propertyCount())
	return "";
	return m_propertySet->propertyAt(i).cssName();
	}

	String PropertySetCSSStyleDeclaration::cssText() const
	{
	return m_propertySet->asText();
	}

	void PropertySetCSSStyleDeclaration::setCSSText(const String& text, ExceptionState& es)
	{
	StyleAttributeMutationScope mutationScope(this);
	willMutate();

	// FIXME: Detect syntax errors and set es.
	m_propertySet->parseDeclaration(text, contextStyleSheet());

	didMutate(PropertyChanged);

	mutationScope.enqueueMutationRecord();
	}

	PassRefPtr<CSSValue> PropertySetCSSStyleDeclaration::getPropertyCSSValue(const String& propertyName)
	{
	CSSPropertyID propertyID = cssPropertyID(propertyName);
	if (!propertyID)
	return 0;
	return cloneAndCacheForCSSOM(m_propertySet->getPropertyCSSValue(propertyID).get());
	}

	String PropertySetCSSStyleDeclaration::getPropertyValue(const String &propertyName)
	{
	CSSPropertyID propertyID = cssPropertyID(propertyName);
	if (!propertyID)
	return String();
	return m_propertySet->getPropertyValue(propertyID);
	}

	String PropertySetCSSStyleDeclaration::getPropertyPriority(const String& propertyName)
	{
	CSSPropertyID propertyID = cssPropertyID(propertyName);
	if (!propertyID)
	return String();
	return m_propertySet->propertyIsImportant(propertyID) ? "important" : "";
	}

	String PropertySetCSSStyleDeclaration::getPropertyShorthand(const String& propertyName)
	{
	CSSPropertyID propertyID = cssPropertyID(propertyName);
	if (!propertyID)
	return String();
	CSSPropertyID shorthandID = m_propertySet->getPropertyShorthand(propertyID);
	if (!shorthandID)
	return String();
	return getPropertyNameString(shorthandID);
	}

	bool PropertySetCSSStyleDeclaration::isPropertyImplicit(const String& propertyName)
	{
	CSSPropertyID propertyID = cssPropertyID(propertyName);
	if (!propertyID)
	return false;
	return m_propertySet->isPropertyImplicit(propertyID);
	}

	void PropertySetCSSStyleDeclaration::setProperty(const String& propertyName, const String& value, const String& priority, ExceptionState& es)
	{
	StyleAttributeMutationScope mutationScope(this);
	CSSPropertyID propertyID = cssPropertyID(propertyName);
	if (!propertyID)
	return;

	bool important = priority.find("important", 0, false) != kNotFound;

	willMutate();

	bool changed = m_propertySet->setProperty(propertyID, value, important, contextStyleSheet());

	didMutate(changed ? PropertyChanged : NoChanges);

	if (changed) {
	// CSS DOM requires raising SyntaxError of parsing failed, but this is too dangerous for compatibility,
	// see <http://bugs.webkit.org/show_bug.cgi?id=7296>.
	mutationScope.enqueueMutationRecord();
	}
	}

	String PropertySetCSSStyleDeclaration::removeProperty(const String& propertyName, ExceptionState& es)
	{
	StyleAttributeMutationScope mutationScope(this);
	CSSPropertyID propertyID = cssPropertyID(propertyName);
	if (!propertyID)
	return String();

	willMutate();

	String result;
	bool changed = m_propertySet->removeProperty(propertyID, &result);

	didMutate(changed ? PropertyChanged : NoChanges);

	if (changed)
	mutationScope.enqueueMutationRecord();
	return result;
	}

	PassRefPtr<CSSValue> PropertySetCSSStyleDeclaration::getPropertyCSSValueInternal(CSSPropertyID propertyID)
	{
	return m_propertySet->getPropertyCSSValue(propertyID);
	}

	String PropertySetCSSStyleDeclaration::getPropertyValueInternal(CSSPropertyID propertyID)
	{
	return m_propertySet->getPropertyValue(propertyID);
	}

	void PropertySetCSSStyleDeclaration::setPropertyInternal(CSSPropertyID propertyID, const String& value, bool important, ExceptionState& es)
	{
	StyleAttributeMutationScope mutationScope(this);
	willMutate();

	bool changed = m_propertySet->setProperty(propertyID, value, important, contextStyleSheet());

	didMutate(changed ? PropertyChanged : NoChanges);

	if (changed)
	mutationScope.enqueueMutationRecord();
	}

	unsigned PropertySetCSSStyleDeclaration::variableCount() const
	{
	ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
	return m_propertySet->variableCount();
	}

	String PropertySetCSSStyleDeclaration::variableValue(const AtomicString& name) const
	{
	ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
	return m_propertySet->variableValue(name);
	}

	bool PropertySetCSSStyleDeclaration::setVariableValue(const AtomicString& name, const String& value, ExceptionState&)
	{
	ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
	StyleAttributeMutationScope mutationScope(this);
	willMutate();
	bool changed = m_propertySet->setVariableValue(name, value);
	didMutate(changed ? PropertyChanged : NoChanges);
	if (changed)
	mutationScope.enqueueMutationRecord();
	return changed;
	}

	bool PropertySetCSSStyleDeclaration::removeVariable(const AtomicString& name)
	{
	ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
	StyleAttributeMutationScope mutationScope(this);
	willMutate();
	bool changed = m_propertySet->removeVariable(name);
	didMutate(changed ? PropertyChanged : NoChanges);
	if (changed)
	mutationScope.enqueueMutationRecord();
	return changed;
	}

	bool PropertySetCSSStyleDeclaration::clearVariables(ExceptionState&)
	{
	ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
	StyleAttributeMutationScope mutationScope(this);
	willMutate();
	bool changed = m_propertySet->clearVariables();
	didMutate(changed ? PropertyChanged : NoChanges);
	if (changed)
	mutationScope.enqueueMutationRecord();
	return changed;
	}

	PassRefPtr<CSSVariablesIterator> PropertySetCSSStyleDeclaration::variablesIterator() const
	{
	return m_propertySet->variablesIterator();
	}

	CSSValue* PropertySetCSSStyleDeclaration::cloneAndCacheForCSSOM(CSSValue* internalValue)
	{
	if (!internalValue)
	return 0;

	// The map is here to maintain the object identity of the CSSValues over multiple invocations.
	// FIXME: It is likely that the identity is not important for web compatibility and this code should be removed.
	if (!m_cssomCSSValueClones)
	m_cssomCSSValueClones = adoptPtr(new HashMap<CSSValue*, RefPtr<CSSValue> >);

	RefPtr<CSSValue>& clonedValue = m_cssomCSSValueClones->add(internalValue, RefPtr<CSSValue>()).iterator->value;
	if (!clonedValue)
	clonedValue = internalValue->cloneForCSSOM();
	return clonedValue.get();
	}

	StyleSheetContents* PropertySetCSSStyleDeclaration::contextStyleSheet() const
	{
	CSSStyleSheet* cssStyleSheet = parentStyleSheet();
	return cssStyleSheet ? cssStyleSheet->contents() : 0;
	}

	PassRefPtr<MutableStylePropertySet> PropertySetCSSStyleDeclaration::copyProperties() const
	{
	return m_propertySet->mutableCopy();
	}

	bool PropertySetCSSStyleDeclaration::cssPropertyMatches(CSSPropertyID propertyID, const CSSValue* propertyValue) const
	{
	return m_propertySet->propertyMatches(propertyID, propertyValue);
	}

	StyleRuleCSSStyleDeclaration::StyleRuleCSSStyleDeclaration(MutableStylePropertySet* propertySet, CSSRule* parentRule)
	: PropertySetCSSStyleDeclaration(propertySet)
	, m_refCount(1)
	, m_parentRule(parentRule)
	{
	m_propertySet->ref();
	}

	StyleRuleCSSStyleDeclaration::~StyleRuleCSSStyleDeclaration()
	{
	m_propertySet->deref();
	}

	void StyleRuleCSSStyleDeclaration::ref()
	{
	++m_refCount;
	}

	void StyleRuleCSSStyleDeclaration::deref()
	{
	ASSERT(m_refCount);
	if (!--m_refCount)
	delete this;
	}

	void StyleRuleCSSStyleDeclaration::willMutate()
	{
	if (m_parentRule && m_parentRule->parentStyleSheet())
	m_parentRule->parentStyleSheet()->willMutateRules();
	}

	void StyleRuleCSSStyleDeclaration::didMutate(MutationType type)
	{
	if (type == PropertyChanged)
	m_cssomCSSValueClones.clear();

	// Style sheet mutation needs to be signaled even if the change failed. willMutateRules/didMutateRules must pair.
	if (m_parentRule && m_parentRule->parentStyleSheet())
	m_parentRule->parentStyleSheet()->didMutateRules();
	}

	CSSStyleSheet* StyleRuleCSSStyleDeclaration::parentStyleSheet() const
	{
	return m_parentRule ? m_parentRule->parentStyleSheet() : 0;
	}

	void StyleRuleCSSStyleDeclaration::reattach(MutableStylePropertySet* propertySet)
	{
	ASSERT(propertySet);
	m_propertySet->deref();
	m_propertySet = propertySet;
	m_propertySet->ref();
	}

	void InlineCSSStyleDeclaration::didMutate(MutationType type)
	{
	if (type == NoChanges)
	return;

	m_cssomCSSValueClones.clear();

	if (!m_parentElement)
	return;

	m_parentElement->setNeedsStyleRecalc(LocalStyleChange);
	m_parentElement->invalidateStyleAttribute();
	StyleAttributeMutationScope(this).didInvalidateStyleAttr();
	}

	CSSStyleSheet* InlineCSSStyleDeclaration::parentStyleSheet() const
	{
	return m_parentElement ? m_parentElement->document().elementSheet() : 0;
	}

	} // namespace WebCore