DOM wrappers that are not retained from Dart should be collected.

Source/WebCore/bindings/dart/DartIsolate.h

Index: Source/WebCore/bindings/dart/DartIsolate.h
diff --git a/Source/WebCore/bindings/dart/DartIsolate.h b/Source/WebCore/bindings/dart/DartIsolate.h
index 8950deed5fd9ec1b1e2183e3d623184502bc3265..c11fc860da57b825c1dbb1f71eced5fe07da3f03 100644
--- a/Source/WebCore/bindings/dart/DartIsolate.h
+++ b/Source/WebCore/bindings/dart/DartIsolate.h
@@ -31,6 +31,7 @@
 #define DartIsolate_h
 
 #include <dart_api.h>
+#include <wtf/HashMap.h>
 #include <wtf/RefPtr.h>
 #include <wtf/ThreadSafeRefCounted.h>
 
@@ -74,10 +75,34 @@ public:
         RefPtr<DartIsolate> m_isolate;
     };
 
+    Dart_Handle createWeakPersistentHandle(Dart_Handle object, void* peer, Dart_WeakPersistentHandleFinalizer);
+
 private:
     DartIsolate(Dart_Isolate);
 
     Dart_Isolate m_isolate;
+
+    static void weakCallbackWrapper(Dart_Handle object, void* peer);

[Anton Muhin, 2012/03/28 18:03:23]

do you really need a map here?  it looks like all you need is to be able to
iterate over all the elements and remove an element, couldn't you use doubly
linked list?

[podivilov, 2012/03/28 18:20:05]

I will need to dispose persistent handles in some cases, e.g. for inspected
values.

+
+    struct WeakCallbackData
+    {
+        WeakCallbackData()
+            : peer(0)
+            , weakCallback(0)
+        {
+        }
+
+        WeakCallbackData(void* peer, Dart_WeakPersistentHandleFinalizer weakCallback)
+            : peer(peer)
+            , weakCallback(weakCallback)
+        {
+        }
+
+        void* peer;
+        Dart_WeakPersistentHandleFinalizer weakCallback;
+    };
+    typedef HashMap<Dart_Handle, WeakCallbackData> WeakCallbackMap;
+    WeakCallbackMap m_weakCallbackMap;
 };