Use toSVGFontElement() instead of static_cast<SVGFontElement*>

Source/core/loader/cache/CachedFont.cpp

Index: Source/core/loader/cache/CachedFont.cpp
diff --git a/Source/core/loader/cache/CachedFont.cpp b/Source/core/loader/cache/CachedFont.cpp
index 782ff17bddec72f85ee4f3bba05d4e396d27afe6..5ae164270e2a049f31d75e777669b0dc7d271b0a 100644
--- a/Source/core/loader/cache/CachedFont.cpp
+++ b/Source/core/loader/cache/CachedFont.cpp
@@ -135,10 +135,10 @@ SVGFontElement* CachedFont::getSVGFontById(const String& fontName) const
 #endif
 
     if (fontName.isEmpty())
-        return static_cast<SVGFontElement*>(list->item(0));
+        return toSVGFontElement(list->item(0));
 
     for (unsigned i = 0; i < listLength; ++i) {
-        SVGFontElement* element = static_cast<SVGFontElement*>(list->item(i));
+        SVGFontElement* element = toSVGFontElement(list->item(i));
         if (element->getIdAttribute() == fontName)
             return element;
     }