Oilpan: fix build after r200992.

Source/core/dom/ScriptedIdleTaskController.cpp

Index: Source/core/dom/ScriptedIdleTaskController.cpp
diff --git a/Source/core/dom/ScriptedIdleTaskController.cpp b/Source/core/dom/ScriptedIdleTaskController.cpp
index b5524e03fad944f605aeba7f29ed2a7b197f04dd..bd4830ce8d902aee7276947f4cab11b0ece47438 100644
--- a/Source/core/dom/ScriptedIdleTaskController.cpp
+++ b/Source/core/dom/ScriptedIdleTaskController.cpp
@@ -67,12 +67,14 @@ ScriptedIdleTaskController::ScriptedIdleTaskController(ExecutionContext* context
     suspendIfNeeded();
 }
 
-DEFINE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(ScriptedIdleTaskController);
+ScriptedIdleTaskController::~ScriptedIdleTaskController()
+{
+}
 
 DEFINE_TRACE(ScriptedIdleTaskController)
 {
-    ActiveDOMObject::trace(visitor);
     visitor->trace(m_callbacks);
+    ActiveDOMObject::trace(visitor);
 }
 
 ScriptedIdleTaskController::CallbackId ScriptedIdleTaskController::registerCallback(IdleRequestCallback* callback, double timeoutMillis)