src/vs/workbench/contrib/tasks/browser/abstractTaskService.ts/AbstractTaskService/migrateRecentTasks
class AbstractTaskService:	private async migrateRecentTasks(tasks: Task[]) {
		if (!this.needsRecentTasksMigration()) {
			return;
		}
		let recentlyUsedTasks = this.getRecentlyUsedTasksV1();
		let taskMap: IStringDictionary<Task> = Object.create(null);
		tasks.forEach(task => {
			let key = task.getRecentlyUsedKey();
			if (key) {
				taskMap[key] = task;
			}
		});
		const reversed = [...recentlyUsedTasks.keys()].reverse();
		for (const key in reversed) {
			let task = taskMap[key];
			if (task) {
				await this.setRecentlyUsedTask(task);
			}
		}
		this.storageService.remove(AbstractTaskService.RecentlyUsedTasks_Key, StorageScope.WORKSPACE);
	}