Have Element::ensureMutableInlineStyle() return a reference

Source/core/css/FontFace.h

 /*
  * Copyright (C) 2013 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 72 matching lines @@
     LoadStatus loadStatus() const { return m_status; }
     void setLoadStatus(LoadStatus);
     unsigned traitsMask() const;
     CSSFontFace* cssFontFace() { return m_cssFontFace.get(); }
 
 private:
     FontFace(PassRefPtrWillBeRawPtr<CSSValue> source);
 
     void initCSSFontFace(Document*);
     void setPropertyFromString(const Document*, const String&, CSSPropertyID, ExceptionState&);
-    bool setPropertyFromStyle(const StylePropertySet*, CSSPropertyID);
+    bool setPropertyFromStyle(const StylePropertySet&, CSSPropertyID);
     bool setPropertyValue(PassRefPtrWillBeRawPtr<CSSValue>, CSSPropertyID);
     bool setFamilyValue(CSSValueList*);
     void resolveReadyPromises();
 
     AtomicString m_family;
     RefPtr<CSSValue> m_src;
     RefPtr<CSSValue> m_style;
     RefPtr<CSSValue> m_weight;
     RefPtr<CSSValue> m_stretch;
     RefPtr<CSSValue> m_unicodeRange;
     RefPtr<CSSValue> m_variant;
     RefPtr<CSSValue> m_featureSettings;
     LoadStatus m_status;
 
     Vector<OwnPtr<FontFaceReadyPromiseResolver> > m_readyResolvers;
     OwnPtr<CSSFontFace> m_cssFontFace;
 };
 
 typedef Vector<RefPtr<FontFace> > FontFaceArray;
 
 } // namespace WebCore
 
 #endif // FontFace_h