Inside

 CanonicalKieModule.createKieBase( KieBaseModelImpl, KieProject, ResultsImpl, KieBaseConfiguration)

there is a call to

 CanonicalKieModule.hasNonModelResources( KieBaseModelImpl, KieProject )

This method returns `true` if there are some dmn and/or pmml files in the project.
If such boolean is `true` a new KnowledgePackagesBuildResult is created.
The main issues with this approach are:
1) managing of dmn/pmml resources is completely hidden inside this boolean method and hard to find in debug
2) it is possible that the new KnowledgePackagesBuildResult build will fire a compilation also of "drl" or other resources that are "compiled" anyway even without this flag