End message event in embedded subprocess doesn't compile.

Compiling with an end event in an embedded subprocess results in

src/main/java/com/ajita/EmbeddedSubProcessEndEventProcess.java (111:6916) : producer_4 cannot be resolved

Looking at the generated source the producer is declared as:

 
@javax.inject.Inject()
com.ajita.EmbeddedSubProcessEndEventMessageProducer_3_4 producer_3_4;
 
and then referenced as:
 
endNode4.action(kcontext -> {
Float object = (Float) kcontext.getVariable("length");
org.drools.core.common.InternalKnowledgeRuntime runtime = (org.drools.core.common.InternalKnowledgeRuntime) kcontext.getKieRuntime();
org.kie.kogito.internal.process.runtime.KogitoProcessInstance pi = (org.kie.kogito.internal.process.runtime.KogitoProcessInstance) kcontext.getProcessInstance();
org.jbpm.process.instance.InternalProcessRuntime process = (org.jbpm.process.instance.InternalProcessRuntime) runtime.getProcessRuntime();
process.getProcessEventSupport().fireOnMessage(pi, kcontext.getNodeInstance(), runtime, "PieceVerified", object);
producer_4.produce(pi, object);
});