Removed unused matching behavior.

Source/core/css/resolver/StyleResolver.h

Index: Source/core/css/resolver/StyleResolver.h
diff --git a/Source/core/css/resolver/StyleResolver.h b/Source/core/css/resolver/StyleResolver.h
index ed2e02a82ac7dd95208262a4a9028122aed4d993..23ec9635c80bba3bc32bf2ab0cc8021ca8ed3016 100644
--- a/Source/core/css/resolver/StyleResolver.h
+++ b/Source/core/css/resolver/StyleResolver.h
@@ -79,13 +79,9 @@ enum StyleSharingBehavior {
     DisallowStyleSharing,
 };
 
-// MatchOnlyUserAgentRules is used in media queries, where relative units
-// are interpreted according to the document root element style, and styled only
-// from the User Agent Stylesheet rules.
 enum RuleMatchingBehavior {
     MatchAllRules,
-    MatchAllRulesExcludingSMIL,
-    MatchOnlyUserAgentRules,
+    MatchAllRulesExcludingSMIL
 };
 
 const unsigned styleSharingListSize = 40;