message: de-duplicate <unnamed> default thread name
diff: @@ -134,16 +134,20 @@ impl<'mir, 'tcx> Thread<'mir, 'tcx> {
  }
  false
  }
  +
  + /// Get the name of the current thread, or `<unnamed>` if it was not set.
  + fn thread_name(&self) -> &[u8] {
  + if let Some(ref thread_name) = self.thread_name {
  + thread_name
  + } else {
  + b"<unnamed>"
  + }
  + }
  }
  impl<'mir, 'tcx> std::fmt::Debug for Thread<'mir, 'tcx> {
  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
  - if let Some(ref name) = self.thread_name {
  - write!(f, "{}", String::from_utf8_lossy(name))?;
  - } else {
  - write!(f, "<unnamed>")?;
  - }
  - write!(f, "({:?}, {:?})", self.state, self.join_status)
  + write!(f, "{}({:?}, {:?})", String::from_utf8_lossy(self.thread_name()), self.state, self.join_status)
  }
  }
  @@ -314,11 +318,7 @@ impl<'mir, 'tcx: 'mir> ThreadManager<'mir, 'tcx> {
  /// Get the name of the active thread.
  fn get_thread_name(&self) -> &[u8] {
  - if let Some(ref thread_name) = self.active_thread_ref().thread_name {
  - thread_name
  - } else {
  - b"<unnamed>"
  - }
  + self.active_thread_ref().thread_name()
  }
  /// Allocate a new blockset id.
  