/guava/android/guava/src/com/google/common/util/concurrent/ExecutionSequencer.java
this.task = null;
this.task = task;
submittingTaskQueue.nextTask = task; submittingTaskQueue.nextExecutor = requireNonNull(delegate); delegate = null; } else { Executor localDelegate = requireNonNull(delegate); delegate = null; <extra_id_0> localDelegate.execute(this); } } finally { submitting = null; } }