message: Disable call to millisleep during file upgrade
diff: @@ -1539,7 +1539,12 @@ void SharedGroup::upgrade_file_format(bool allow_file_format_upgrade,
  // a simple thread barrier that makes sure the threads meet here, to
  // increase the likelyhood of detecting any potential race problems.
  // See the unit test for details.
  - millisleep(200);
  +//
  +// NOTE: This sleep has been disabled because no problems have been found with
  +// this code in a long while, and it was dramatically slowing down a unit test
  +// in realm-sync.
  +
  + // millisleep(200);
  #endif
  WriteTransaction wt(*this);
  