DrlDumper does not output binding for accumulate function

When building a rule with a single-function accumulate conditional element, I set the binding name for the function call according to the documentation for the function method of the AccumulateDescrBuilder. However, when the function is output by the DrlDumper, the accumulate call is output without the binding.

I've traced the Builder to the Descr and that sets the description correctly. The problem seems to be with the drl.mvel template, line 96, the function output template doesn't have a marker for the binding name. (https://github.com/droolsjbpm/drools/blob/master/drools-compiler/src/main/resources/org/drools/compiler/lang/drl.mvel)