Form with Address containing state/province throws error

Problem/Motivation

This issues described two (related) issues:

1. Filling out a form with input fields for country, state/province and district/country throws an error if only country and state/province are filled out.
2. Filling out a form with input fields for country, state/province and email throws an error.

Detailed steps to reproduce (issue 1)

Configure form

1. CiviCRM → Check Enable CiviCRM Processing
2. Number of Contacts: 1
3. 1. Contact 1? → Number of Address Fields: 1
4. Address 1 (Primary) → Choose Country, State/Province and District/County

Fill form

1. Country: Malaysia
2. State/Province: Selangor
3. District/County: - First Choose a State -
4. Submit

Receive error inside logs

• Location: https://<domain>/webform-civicrm/js/county/10-1131
• Message: CiviCRM_API3_Exception: Expected one StateProvince but found 0 in civicrm_api3() (line 134 of /var/www/<domain>/vendor/civicrm/civicrm-core/api/api.php).
• Severity: Error

Detailed steps to reproduce (issue 2)

Configure form

1. CiviCRM → Check Enable CiviCRM Processing
2. Number of Contacts: 1
3. 1. Contact 1? → Number of Address Fields: 1
4. Address 1 (Primary) → Choose Country and State/Province
5. 1. Contact 1? → Number of Email Fields: 1

Fill form

1. Country: Malaysia
2. State/Province: Selangor
3. Email: anything, e.g. test@invalid
4. Submit

Receive errors

Forms dooes not show a submission message, but only says "The website encountered an unexpected error. Please try again later.".

The following errors appear in the log:

Error 1

• Type: webform_submission
• Message: CiviCRM_API3_Exception: Expected one StateProvince but found 0 in civicrm_api3() (line 134 of /var/www/<domain>/vendor/civicrm/civicrm-core/api/api.php).
• Severity: Error

Error 2

• Type: php
• Message: Drupal\Core\Entity\EntityStorageException: Expected one StateProvince but found 0 in Drupal\Core\Entity\Sql\SqlContentEntityStorage->save() (line 810 of /var/www/<domain>/web/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php).
• Severity: Error

Proposed resolution

Do not throw an error.