wp-admin/includes/class-bulk-upgrader-skin.php:60Sets up the strings used in the update process.
public function add_strings() { $this->upgrader->strings['skin_upgrade_start'] = __( 'The update process is starting. This process may take a while on some hosts, so please be patient.' ); /* translators: 1: Title of an update, 2: Error message. */ $this->upgrader->strings['skin_update_failed_error'] = __( 'An error occurred while updating %1$s: %2$s' ); /* translators: %s: Title of an update. */ $this->upgrader->strings['skin_update_failed'] = __( 'The update of %s failed.' ); /* translators: %s: Title of an update. */ $this->upgrader->strings['skin_update_successful'] = __( '%s updated successfully.' ); $this->upgrader->strings['skin_upgrade_end'] = __( 'All updates have been completed.' ); }Introduced in 3.0.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-admin/includes/class-bulk-upgrader-skin.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.