Backend for css rule tracking

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 929d3746dc01eb1304b872bf53906bab8ba01b26..d393df2004d09a17048a4e1e8f422bc5d9800ad4 100644
--- a/third_party/WebKit/Source/core/css/resolver/StyleResolver.h
+++ b/third_party/WebKit/Source/core/css/resolver/StyleResolver.h
@@ -58,6 +58,7 @@ class MediaQueryEvaluator;
 class ScopedStyleResolver;
 class StylePropertySet;
 class StyleRule;
+class StyleRuleUsageTracker;
 
 enum StyleSharingBehavior {
   AllowStyleSharing,
@@ -194,6 +195,8 @@ class CORE_EXPORT StyleResolver final
 
   void initWatchedSelectorRules();
 
+  void setRuleUsageTracker(StyleRuleUsageTracker*);
+
  private:
   explicit StyleResolver(Document&);
 
@@ -202,6 +205,8 @@ class CORE_EXPORT StyleResolver final
   // FIXME: This should probably go away, folded into FontBuilder.
   void updateFont(StyleResolverState&);
 
+  void addMatchedRulesToTracker(const ElementRuleCollector&);
+
   void loadPendingResources(StyleResolverState&);
   void adjustComputedStyle(StyleResolverState&, Element*);
 
@@ -285,6 +290,8 @@ class CORE_EXPORT StyleResolver final
   Member<RuleSet> m_uncommonAttributeRuleSet;
   Member<RuleSet> m_watchedSelectorsRules;
 
+  Member<StyleRuleUsageTracker> m_tracker;
+
   bool m_needCollectFeatures;
   bool m_printMediaType;
   bool m_hasFullscreenUAStyle = false;