Can't add shipping to manual orders when coupons enabled

If you have a coupon and discount set up, when you try to create a manual order and then add shipping as an option, it throws an ajax error:

PDOException: SQLSTATE[HY000]: General error: 1366 Incorrect integer value: '' for column 'commerce_coupons_target_id' at row 1: INSERT INTO {field_data_commerce_coupons} (entity_type, entity_id, revision_id, bundle, delta, language, commerce_coupons_target_id) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3, :db_insert_placeholder_4, :db_insert_placeholder_5, :db_insert_placeholder_6); Array ( [:db_insert_placeholder_0] => commerce_order [:db_insert_placeholder_1] => 615 [:db_insert_placeholder_2] => 1764 [:db_insert_placeholder_3] => commerce_order [:db_insert_placeholder_4] => 0 [:db_insert_placeholder_5] => und [:db_insert_placeholder_6] => ) in field_sql_storage_field_storage_write() (line 514 of /modules/field/modules/field_sql_storage/field_sql_storage.module).

Attached patch fixes