Rework MediaQueryMatcher to batch up listener notification

Source/core/css/MediaQueryList.h

Index: Source/core/css/MediaQueryList.h
diff --git a/Source/core/css/MediaQueryList.h b/Source/core/css/MediaQueryList.h
index e832f29dde4bb242cb5f676ee774639fb81e3c4d..30af2cf0ad455891dcf432f52bf8a010f5182c89 100644
--- a/Source/core/css/MediaQueryList.h
+++ b/Source/core/css/MediaQueryList.h
@@ -38,27 +38,33 @@ class MediaQuerySet;
 // will be called whenever the value of the query changes.
 
 class MediaQueryList FINAL : public RefCountedWillBeGarbageCollected<MediaQueryList> {
-    DECLARE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(MediaQueryList);
 public:
-    static PassRefPtrWillBeRawPtr<MediaQueryList> create(PassRefPtrWillBeRawPtr<MediaQueryMatcher>, PassRefPtrWillBeRawPtr<MediaQuerySet>, bool);
+    static PassRefPtrWillBeRawPtr<MediaQueryList> create(PassRefPtrWillBeRawPtr<MediaQueryMatcher>, PassRefPtrWillBeRawPtr<MediaQuerySet>);
     String media() const;
     bool matches();
 
     void addListener(PassRefPtrWillBeRawPtr<MediaQueryListListener>);
     void removeListener(PassRefPtrWillBeRawPtr<MediaQueryListListener>);
 
-    bool evaluate(MediaQueryEvaluator*);
+    void mediaChanged(WillBeHeapVector<RefPtrWillBeMember<MediaQueryListListener> > toNotify);
 
     void trace(Visitor*);
 
+    void documentDetached();
+
 private:
-    MediaQueryList(PassRefPtrWillBeRawPtr<MediaQueryMatcher>, PassRefPtrWillBeRawPtr<MediaQuerySet>, bool matches);
-    void setMatches(bool);
+    MediaQueryList(PassRefPtrWillBeRawPtr<MediaQueryMatcher>, PassRefPtrWillBeRawPtr<MediaQuerySet>);
+    ~MediaQueryList();
+
+    bool updateMatches();
 
     RefPtrWillBeMember<MediaQueryMatcher> m_matcher;
     RefPtrWillBeMember<MediaQuerySet> m_media;
-    unsigned m_evaluationRound; // Indicates if the query has been evaluated after the last style selector change.
-    unsigned m_changeRound; // Used to know if the query has changed in the last style selector change.
+
+    // FIXME: This should be a HeapListHashSet when oilpan supports it.
+    ListHashSet<RefPtrWillBePersistent<MediaQueryListListener> > m_listeners;
+
+    bool m_matchesDirty;
     bool m_matches;
 };