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

Source/WebCore/bindings/dart/DartUtilities.cpp

Index: Source/WebCore/bindings/dart/DartUtilities.cpp
diff --git a/Source/WebCore/bindings/dart/DartUtilities.cpp b/Source/WebCore/bindings/dart/DartUtilities.cpp
index 12210b23928436328a770c1f314d37d4f68b1fa6..3bddac4956c55f4809ec651812a55db5c9f55e86 100644
--- a/Source/WebCore/bindings/dart/DartUtilities.cpp
+++ b/Source/WebCore/bindings/dart/DartUtilities.cpp
@@ -262,7 +262,7 @@ static DartDOMData* domDataForIsolate(Dart_Isolate isolate)
 
 static DartDOMData* currentDOMData()
 {
-    return domDataForIsolate(DartIsolate::current()->isolate());
+    return domDataForIsolate(Dart_CurrentIsolate());
 }
 
 void DartUtilities::registerDOMIsolate(Dart_Isolate isolate, PassRefPtr<DartApplicationLoader> applicationLoader, ScriptExecutionContext* context)
@@ -382,6 +382,43 @@ PassRefPtr<ScriptCallStack> DartUtilities::createScriptCallStack()
     return ScriptCallStack::create(wrappedCallFrames);
 }
 
+class WeakCallbackData
+{
+public:
+    void* peer;
+    Dart_WeakPersistentHandleFinalizer weakCallback;
+    Dart_Handle object;
+};
+
+static void weakCallbackWrapper(Dart_Handle object, void* peer)
+{
+    WeakCallbackData* callbackData = static_cast<WeakCallbackData*>(peer);
+    DartUtilities::domDataForCurrentIsolate()->weakCallbacks()->remove(callbackData);

[Anton Muhin, 2012/03/29 19:18:45]

maybe performance FIXME?  linear search looks scary

[podivilov, 2012/03/30 10:36:28]

weakCallbacks is HashSet, not vector.

+    (*callbackData->weakCallback)(object, callbackData->peer);
+    delete callbackData;
+}
+
+Dart_Handle DartUtilities::createWeakPersistentHandle(Dart_Handle object, void* peer, Dart_WeakPersistentHandleFinalizer weakCallback)
+{
+    WeakCallbackData* callbackData = new WeakCallbackData;

[Anton Muhin, 2012/03/29 19:18:45]

why not provide a ctor in the class itself?

[podivilov, 2012/03/30 10:36:28]

Done.

+    callbackData->peer = peer;
+    callbackData->weakCallback = weakCallback;
+    callbackData->object = Dart_NewWeakPersistentHandle(object, callbackData, &weakCallbackWrapper);
+    domDataForCurrentIsolate()->weakCallbacks()->add(callbackData);
+    return callbackData->object;
+}
+
+void DartUtilities::disposeWeakPersistentHandles()
+{
+    DartWeakCallbacks* weakCallbacks = domDataForCurrentIsolate()->weakCallbacks();
+    for (DartWeakCallbacks::iterator it = weakCallbacks->begin(); it != weakCallbacks->end(); ++it) {
+        WeakCallbackData* callbackData = *it;
+        (*callbackData->weakCallback)(callbackData->object, callbackData->peer);
+        delete callbackData;
+    }
+    weakCallbacks->clear();
+}
+
 const uint8_t* DartUtilities::fullSnapshot()
 {
     static const uint8_t snapshotBuffer[] = {