Clear mutable inline style when it is empty.

Source/core/css/InlineVariablesIterator.h

Index: Source/core/css/InlineVariablesIterator.h
diff --git a/Source/core/svg/SVGFEPointLightElement.h b/Source/core/css/InlineVariablesIterator.h
similarity index 62%
copy from Source/core/svg/SVGFEPointLightElement.h
copy to Source/core/css/InlineVariablesIterator.h
index b32b9516fb980de708812c7afd3ff6ba3ef37df0..2bee919599d77d436ee167bc28418e63853021a2 100644
--- a/Source/core/svg/SVGFEPointLightElement.h
+++ b/Source/core/css/InlineVariablesIterator.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2005 Oliver Hunt <ojh16@student.canterbury.ac.nz>
+ * Copyright (C) 2013 Google Inc. 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
@@ -17,23 +17,26 @@
  * Boston, MA 02110-1301, USA.
  */
 
-#ifndef SVGFEPointLightElement_h
-#define SVGFEPointLightElement_h
+#ifndef InlineVariablesIterator_h
+#define InlineVariablesIterator_h
 
-#include "core/svg/SVGFELightElement.h"
+#include "core/css/VariablesIterator.h"
 
 namespace WebCore {
 
-class SVGFEPointLightElement FINAL : public SVGFELightElement {
+class Element;
+
+// A CSSVariablesIterator implementation for the inline style of an element.

[eseidel, 2013/12/23 23:26:28]

Odd.  So the only thing this provides is mapping from an element to its property
set?  Strange that we don't have a more generic way to do that that we just
provide to a generic iterator.

[chrishtr, 2013/12/23 23:54:51]

I think it's maybe because of non-standard semantics. In particular, if you add
stuff while iterating it will include the stuff you added at the end. (I noticed
that part while debugging a failing test last week.)

+class InlineVariablesIterator : public AbstractVariablesIterator {
 public:
-    static PassRefPtr<SVGFEPointLightElement> create(Document&);
+    explicit InlineVariablesIterator(Element*);
 
 private:
-    explicit SVGFEPointLightElement(Document&);
+    virtual MutableStylePropertySet* propertySet() const OVERRIDE;
 
-    virtual PassRefPtr<LightSource> lightSource() const;
+    RefPtr<Element> m_element;
 };
 
 } // namespace WebCore
 
-#endif
+#endif // InlineVariablesIterator_h