Clear mutable inline style when it is empty.

Source/core/css/PropertySetCSSStyleDeclaration.h

 /*
  * Copyright (C) 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 28 matching lines @@
 class ExceptionState;
 class MutableStylePropertySet;
 class StyleSheetContents;
 
 class AbstractPropertySetCSSStyleDeclaration : public CSSStyleDeclaration {
 public:
     virtual Element* parentElement() const { return 0; }
     virtual void clearParentElement() { ASSERT_NOT_REACHED(); }
     StyleSheetContents* contextStyleSheet() const;
 
+protected:
+    virtual PassRefPtr<CSSVariablesIterator> variablesIterator() const OVERRIDE;
+
 private:
     virtual CSSRule* parentRule() const OVERRIDE { return 0; };
     virtual unsigned length() const OVERRIDE;
     virtual String item(unsigned index) const OVERRIDE;
     virtual PassRefPtr<CSSValue> getPropertyCSSValue(const String& propertyName) OVERRIDE;
     virtual String getPropertyValue(const String& propertyName) OVERRIDE;
     virtual String getPropertyPriority(const String& propertyName) OVERRIDE;
     virtual String getPropertyShorthand(const String& propertyName) OVERRIDE;
     virtual bool isPropertyImplicit(const String& propertyName) OVERRIDE;
     virtual void setProperty(const String& propertyName, const String& value, const String& priority, ExceptionState&) OVERRIDE;
     virtual String removeProperty(const String& propertyName, ExceptionState&) OVERRIDE;
     virtual String cssText() const OVERRIDE;
     virtual void setCSSText(const String&, ExceptionState&) OVERRIDE;
     virtual PassRefPtr<CSSValue> getPropertyCSSValueInternal(CSSPropertyID) OVERRIDE;
     virtual String getPropertyValueInternal(CSSPropertyID) OVERRIDE;
     virtual void setPropertyInternal(CSSPropertyID, const String& value, bool important, ExceptionState&) OVERRIDE;
 
     virtual unsigned variableCount() const OVERRIDE;
     virtual String variableValue(const AtomicString& name) const OVERRIDE;
     virtual bool setVariableValue(const AtomicString& name, const String& value, ExceptionState&) OVERRIDE;
     virtual bool removeVariable(const AtomicString& name) OVERRIDE;
     virtual bool clearVariables(ExceptionState&) OVERRIDE;
-    virtual PassRefPtr<CSSVariablesIterator> variablesIterator() const OVERRIDE;
 
     virtual bool cssPropertyMatches(CSSPropertyID, const CSSValue*) const OVERRIDE;
     virtual PassRefPtr<MutableStylePropertySet> copyProperties() const OVERRIDE;
 
     CSSValue* cloneAndCacheForCSSOM(CSSValue*);
 
 protected:
     enum MutationType { NoChanges, PropertyChanged };
     virtual void willMutate() { }
     virtual void didMutate(MutationType) { }
@@ skipping 47 matching lines @@
 
 class InlineCSSStyleDeclaration : public AbstractPropertySetCSSStyleDeclaration
 {
 public:
     explicit InlineCSSStyleDeclaration(Element* parentElement)
         : m_parentElement(parentElement)
     {
     }
 
 private:
+    virtual PassRefPtr<CSSVariablesIterator> variablesIterator() const OVERRIDE;
     virtual MutableStylePropertySet* propertySet() const OVERRIDE;
     virtual void ref() OVERRIDE;
     virtual void deref() OVERRIDE;
     virtual CSSStyleSheet* parentStyleSheet() const OVERRIDE;
     virtual Element* parentElement() const OVERRIDE { return m_parentElement; }
     virtual void clearParentElement() OVERRIDE { m_parentElement = 0; }
 
     virtual void didMutate(MutationType) OVERRIDE;
 
     Element* m_parentElement;
 };
 
 } // namespace WebCore
 
 #endif