Warnings on CRM_Contribute_Import_Parser re countable

on 5.15.alpha1 on dmaster May 29, testing an import of contributions on step 2 of 4 I get:

Warning: count(): Parameter must be an array or an object that implements Countable in CRM_Contribute_Import_Parser->setActiveFieldSoftCredit() (line 433 of /srv/buildkit/build/dmaster/sites/all/modules/civicrm/CRM/Contribute/Import/Parser.php). Warning: count(): Parameter must be an array or an object that implements Countable in CRM_Contribute_Import_Parser->setActiveFieldSoftCreditType() (line 442 of /srv/buildkit/build/dmaster/sites/all/modules/civicrm/CRM/Contribute/Import/Parser.php).

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