Bug in CompiledChainImpl.buildChain function

The function shows a wrong operation in log, which creates an error.
For instance, the following chain called from a workflow

<chain id="wf_OSA_getParticipants">
<operation id="Context.FetchDocument"/>
<operation id="Auth.LoginAs">
<param type="string" name="name">expr:workflowInitiator</param>
</operation>
<operation id="Document.Lock"/>
<operation id="Document.GetUsersAndGroups">
<param type="string" name="permission">mypermission</param>
<param type="string" name="variable name">assignees</param>
<param type="boolean" name="ignore groups">false</param>
<param type="boolean" name="prefix identifiers">false</param>
<param type="boolean" name="resolve groups">false</param>
</operation>
<operation id="Context.SetWorkflowVar">
<param type="string" name="name">abcd</param>
<param type="object" name="value">expr:workflowInitiator</param>
</operation>
</chain>

generates the error:
"Cannot find any valid path in operation chain - no method found for operation 'Context.SetWorkflowVar' and for first input type 'org.nuxeo.ecm.core.api.impl.DocumentModelListImpl'"

But it can be removed by comment the "Document.GetUsersAndGroups" operation.
So, "Context.SetWorkflowVar" works properly and the problem is in the previous operation.