[PHP ≥ 7.2] "session_id(): Cannot change session id"

After upgrade to 7.2, watchdog log got swamped with these messages:

Warning: session_id(): Cannot change session id when headers already sent in drupal_session_initialize() (line 266 of includes/session.inc).
Warning: session_set_save_handler(): Cannot change save handler when headers already sent in drupal_session_initialize() (line 242 of includes/session.inc).

There is a related issue for drupal core, for the statistics module.
https://www.drupal.org/project/drupal/issues/3009351

Based on this patch, the solution appear to be to take out this line:
visitors.exit.inc #164
drupal_bootstrap(DRUPAL_BOOTSTRAP_SESSION);

I did this, and now everything seems to run normally again, also I am not seeing any errors as far as behavior for visitors.

I set this to major, because 1) the core patch was also major and 2) it really swamped the logs, especially on a busy site.