Do not propagate empty value for face attribute

Source/core/html/HTMLFontElement.cpp

Index: Source/core/html/HTMLFontElement.cpp
diff --git a/Source/core/html/HTMLFontElement.cpp b/Source/core/html/HTMLFontElement.cpp
index a3edaf0fe16af4147420b77f085add0568c0d3f8..4f186fa7fef6681f3382309338388c1c64371c81 100644
--- a/Source/core/html/HTMLFontElement.cpp
+++ b/Source/core/html/HTMLFontElement.cpp
@@ -188,7 +188,7 @@ void HTMLFontElement::collectStyleForPresentationAttribute(const QualifiedName&
             addPropertyToPresentationAttributeStyle(style, CSSPropertyFontSize, size);
     } else if (name == colorAttr)
         addHTMLColorToStyle(style, CSSPropertyColor, value);
-    else if (name == faceAttr) {
+    else if (name == faceAttr && !value.isEmpty()) {
         if (RefPtrWillBeRawPtr<CSSValueList> fontFaceValue = cssValuePool().createFontFaceValue(value))
             style->setProperty(CSSProperty(CSSPropertyFontFamily, fontFaceValue.release()));
     } else