Replace CSSParserString with StringView.

third_party/WebKit/Source/core/css/parser/CSSPropertyParser.h

Index: third_party/WebKit/Source/core/css/parser/CSSPropertyParser.h
diff --git a/third_party/WebKit/Source/core/css/parser/CSSPropertyParser.h b/third_party/WebKit/Source/core/css/parser/CSSPropertyParser.h
index 62c75376d7197f9a7fbd366c9bad1b4d1040bd1c..3d57a64e6168b217ae0790433b5e5c47f0e5eae4 100644
--- a/third_party/WebKit/Source/core/css/parser/CSSPropertyParser.h
+++ b/third_party/WebKit/Source/core/css/parser/CSSPropertyParser.h
@@ -25,10 +25,10 @@
 
 #include "core/css/StyleRule.h"
 #include "core/css/parser/CSSParserTokenRange.h"
+#include "wtf/text/StringView.h"
 
 namespace blink {
 
-struct CSSParserString;
 class CSSProperty;
 class CSSValue;
 class StylePropertyShorthand;
@@ -108,8 +108,8 @@ private:
     HeapVector<CSSProperty, 256>* m_parsedProperties;
 };
 
-CSSPropertyID unresolvedCSSPropertyID(const CSSParserString&);
-CSSValueID cssValueKeywordID(const CSSParserString&);
+CSSPropertyID unresolvedCSSPropertyID(StringView);
+CSSValueID cssValueKeywordID(StringView);
 
 } // namespace blink