mark all remaining placeable tasks pending with task dependency manager (#2528)

src/ray/raylet/node_manager.cc

@@ -750,6 +750,14 @@ void NodeManager::ScheduleTasks() {
       EnqueuePlaceableTask(t);
     }
   }
+
+  // All remaining placeable tasks should be registered with the task dependency
+  // manager. TaskDependencyManager::TaskPending() is assumed to be idempotent.
+  // TODO(atumanov): evaluate performance implications of registering all new tasks on
+  // submission vs. registering remaining queued placeable tasks here.
+  for (const auto &task : local_queues_.GetPlaceableTasks()) {
+    task_dependency_manager_.TaskPending(task);
+  }
 }
 
 void NodeManager::TreatTaskAsFailed(const TaskSpecification &spec) {