Support merged Dart-JS callstacks

Source/bindings/dart/DartController.cpp

Index: Source/bindings/dart/DartController.cpp
diff --git a/Source/bindings/dart/DartController.cpp b/Source/bindings/dart/DartController.cpp
index e816dbe585755b57d9cae02f000a8bdce189e7a5..972e76ecc0893605c3ec2e595331293a9201c968 100644
--- a/Source/bindings/dart/DartController.cpp
+++ b/Source/bindings/dart/DartController.cpp
@@ -234,7 +234,7 @@ void DartController::shutdownIsolate(Dart_Isolate isolate)
     ASSERT(domData->isDOMEnabled());
     // If the following assert triggers, we have hit dartbug.com/14183
     // FIXME: keep the isolate alive until the recursion level is 0.
-    ASSERT(!*(domData->recursion()));
+    ASSERT(!domData->stackTraceTimestampTracker()->recursionLevel());
     DartScriptDebugServer::shared().unregisterIsolate(isolate, m_frame->page());
     DartIsolateDestructionObservers* observers = domData->isolateDestructionObservers();
     for (DartIsolateDestructionObservers::iterator it = observers->begin(); it != observers->end(); ++it)