Unsupported operand types in rules.export.inc when using features

While setting rules features export, I ran into the following js error when ticking "Rule configuration by category" in the add feature page:

Fatal error:  Unsupported operand types in ..../sites/all/modules/rules/rules/rules.export.inc on line 204

It seems the '#conditions' key is missing from $rule in rules_features_process_rule() and therefore the variable $element passed to _rules_features_process_rule() is NULL, hence the error above. Adding a condition to all the rules being exported fix this. It seems this problem does not happen if there are no actions in a rule.