Use count strings as keyframes/animation-name identifiers

Source/core/css/parser/CSSPropertyParser.cpp

Index: Source/core/css/parser/CSSPropertyParser.cpp
diff --git a/Source/core/css/parser/CSSPropertyParser.cpp b/Source/core/css/parser/CSSPropertyParser.cpp
index ce1cf8d1247902b8c16b7aaf9267437e21f48118..4e302b4ee1b8b220296db2812d8978941221cdfc 100644
--- a/Source/core/css/parser/CSSPropertyParser.cpp
+++ b/Source/core/css/parser/CSSPropertyParser.cpp
@@ -2924,6 +2924,8 @@ PassRefPtrWillBeRawPtr<CSSValue> CSSPropertyParser::parseAnimationName()
     CSSParserValue* value = m_valueList->current();
     // FIXME: Strings are not valid as per spec
     if (value->unit == CSSPrimitiveValue::CSS_STRING || value->unit == CSSPrimitiveValue::CSS_IDENT) {
+        if (value->unit == CSSPrimitiveValue::CSS_STRING)
+            m_context.useCounter()->count(UseCounter::QuotedAnimationName);
         if (value->id == CSSValueNone || (value->unit == CSSPrimitiveValue::CSS_STRING && equalIgnoringCase(value->string, "none")))
             return cssValuePool().createIdentifierValue(CSSValueNone);
         return createPrimitiveStringValue(value);