Separate @viewport from other RuleSet construction.

third_party/WebKit/Source/core/css/resolver/StyleResolver.h

Index: third_party/WebKit/Source/core/css/resolver/StyleResolver.h
diff --git a/third_party/WebKit/Source/core/css/resolver/StyleResolver.h b/third_party/WebKit/Source/core/css/resolver/StyleResolver.h
index b63006e0da39b6757225c100b459e2f05f24a5db..47dbe772549735b9e270be5d55fd2300a653306a 100644
--- a/third_party/WebKit/Source/core/css/resolver/StyleResolver.h
+++ b/third_party/WebKit/Source/core/css/resolver/StyleResolver.h
@@ -59,7 +59,6 @@ class MediaQueryEvaluator;
 class ScopedStyleResolver;
 class StylePropertySet;
 class StyleRule;
-class ViewportStyleResolver;
 
 enum StyleSharingBehavior {
   AllowStyleSharing,
@@ -155,10 +154,6 @@ class CORE_EXPORT StyleResolver final
 
   void computeFont(ComputedStyle*, const StylePropertySet&);
 
-  ViewportStyleResolver* viewportStyleResolver() {
-    return m_viewportStyleResolver.get();
-  }
-
   void addViewportDependentMediaQueries(const MediaQueryResultList&);
   bool hasViewportDependentMediaQueries() const {
     return !m_viewportDependentMediaQueryResults.isEmpty();
@@ -282,8 +277,6 @@ class CORE_EXPORT StyleResolver final
   Member<Document> m_document;
   SelectorFilter m_selectorFilter;
 
-  Member<ViewportStyleResolver> m_viewportStyleResolver;
-
   HeapListHashSet<Member<CSSStyleSheet>, 16> m_pendingStyleSheets;
 
   // FIXME: The entire logic of collecting features on StyleResolver, as well as