Clear mutable inline style when it is empty.

Source/core/css/InlineVariablesIterator.cpp

Index: Source/core/css/InlineVariablesIterator.cpp
diff --git a/Source/core/css/resolver/MediaQueryResult.h b/Source/core/css/InlineVariablesIterator.cpp
similarity index 57%
copy from Source/core/css/resolver/MediaQueryResult.h
copy to Source/core/css/InlineVariablesIterator.cpp
index 1dc00f42dc31c621d290407328d06229fc0e58ff..b5197d1d7745f70f931aefce156e666a7852b1d4 100644
--- a/Source/core/css/resolver/MediaQueryResult.h
+++ b/Source/core/css/InlineVariablesIterator.cpp
@@ -1,6 +1,4 @@
 /*
- * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
- * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
@@ -17,31 +15,33 @@
  * 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.
- *
  */
 
-#ifndef MediaQueryResult_h
-#define MediaQueryResult_h
+#include "config.h"
+#include "core/css/InlineVariablesIterator.h"
 
-#include "core/css/MediaQueryExp.h"
-#include "wtf/Noncopyable.h"
-#include "wtf/RefCounted.h"
+#include "RuntimeEnabledFeatures.h"
+#include "core/css/CSSVariableValue.h"
+#include "core/css/StylePropertySet.h"
+#include "core/dom/Element.h"
 
 namespace WebCore {
 
-class MediaQueryResult : public RefCounted<MediaQueryResult> {
-    WTF_MAKE_NONCOPYABLE(MediaQueryResult); WTF_MAKE_FAST_ALLOCATED;
-public:
-    MediaQueryResult(const MediaQueryExp& expr, bool result)
-        : m_expression(expr)
-        , m_result(result)
-    {
+InlineVariablesIterator::InlineVariablesIterator(Element* element)
+    : m_element(element)
+{
+    ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
+
+    const StylePropertySet* propertySet = element->inlineStyle();
+    if (propertySet) {
+        initRemainingNames(propertySet);
     }
+}
 
-    MediaQueryExp m_expression;
-    bool m_result;
-};
 
+MutableStylePropertySet* InlineVariablesIterator::propertySet() const
+{
+    return m_element->ensureMutableInlineStyle();
 }
 
-#endif
+} // namespace WebCore