NO-ISSUE: DMN Editor: Prevent from 'Include model' click in case of empty model

[jomarko]

Before

Imagine there is folder with two DMN model and both are empty - there is no node or custom data type defined in them. That is a similar to situation to early phase of any project.

Now please follow these steps.

• lets say models have names a.dmn and b.dmn
• open the model a
• click the included models tab
• try to import the model b
• you will be in situation like shown in the attached screenshot
• then press Include model button - Here is the issue, nothing happens

and there will be an error in js console

Now

User is prevented from clicking 'Include model' in case the model can not be included.

[Josephblt]

Working great, both for empty models and valid ones.

[tiagobento]

Please use the kie-dmn-editor-- prefix

[jomarko]

Sure, good point, added in new commit.