Support meta annotation for @ThreadSafe #6042

Hi, I would like to ask whether meta annotation is supported for the @ThreadSafe annotation.

The background is that I am trying to integrate both the Error Prone and fbinfer RacerD @ThreadSafe annotation (https://fbinfer.com/docs/checker-racerd) into a unified ThreadSafe annotation that composes both of them.

@com.google.errorprone.annotations.ThreadSafe
@com.facebook.infer.annotation.ThreadSafe
public @interface ThreadSafe {}

This way, we do not need to have two @ThreadSafe annotation for the same class. However, I'm not sure if this is supported by error-prone project.

Thanks in advance. Apologies if this issue has been asked before.