Call media query change listeners asynchronously.

Source/core/css/MediaQueryMatcher.h

Index: Source/core/css/MediaQueryMatcher.h
diff --git a/Source/core/css/MediaQueryMatcher.h b/Source/core/css/MediaQueryMatcher.h
index be12559b9f693cc8fa63bbef80a7e7d6a3b62f03..1e264f08d5e31d1147d3bf3e36b3d55334126e04 100644
--- a/Source/core/css/MediaQueryMatcher.h
+++ b/Source/core/css/MediaQueryMatcher.h
@@ -20,6 +20,7 @@
 #ifndef MediaQueryMatcher_h
 #define MediaQueryMatcher_h
 
+#include "core/css/MediaQueryList.h"
 #include "platform/heap/Handle.h"
 #include "wtf/Forward.h"
 #include "wtf/RefCounted.h"
@@ -52,6 +53,9 @@ public:
     void mediaFeaturesChanged();
     bool evaluate(const MediaQuerySet*);
 
+    void notifyDelayedListeners();
+    bool hasDelayedListeners() const { return m_delayedListeners.size(); }
+
     void trace(Visitor*);
 
 private:
@@ -62,6 +66,8 @@ private:
     RawPtrWillBeMember<Document> m_document;
     OwnPtr<MediaQueryEvaluator> m_evaluator;
 
+    WillBeHeapVector<RefPtrWillBeMember<MediaQueryList::Listener> > m_delayedListeners;
+
     typedef WillBeHeapLinkedHashSet<RawPtrWillBeWeakMember<MediaQueryList> > MediaQueryListSet;
     MediaQueryListSet m_mediaLists;
 };