Prevent CCE NbGradleProjectImpl to DataObject

[lkishalmi]

Playing with Ernies composite build in #4865 I've encountered the following exception

java.lang.ClassCastException: class org.netbeans.modules.gradle.NbGradleProjectImpl cannot be cast to class org.openide.loaders.DataObject (org.netbeans.modules.gradle.NbGradleProjectImpl is in unnamed module of loader org.netbeans.StandardModule$OneModuleClassLoader @512bad4a; org.openide.loaders.DataObject is in unnamed module of loader org.netbeans.StandardModule$OneModuleClassLoader @657680c2)
	at org.netbeans.modules.editor.hints.HintsControllerImpl.setErrors(HintsControllerImpl.java:68)
	at org.netbeans.spi.editor.hints.HintsController$1.run(HintsController.java:59)
	at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1418)
	at org.netbeans.modules.openide.util.GlobalLookup.execute(GlobalLookup.java:45)

It seems some other NetBeans parts expecting a DataObject in a Document Document.StreamDescriptionProperty as Stream descriptor. I used that property ages ago probably seen that on some other editor. This PR just change the property name used for the code completion provider.

It seems if this exception does not happen, then the registration of the JDPA listener would g through, fixing #4865 entirely.

[mbien]

gh might be having issues since I can't label this PR (or other PRs). Unfortunately this means the Gradle tests won't run.

nevermind. was a temporary issue. Restarted the build.

[mbien]

makes sense + looks like a fairly low risk change

[lkishalmi]

gh might be having issues since I can't label this PR (or other PRs). Unfortunately this means the Gradle tests won't run.

nevermind. was a temporary issue. Restarted the build.

Oh, I knew I forgot something! I'm sorry.

[sdedic]

It seems some other NetBeans parts expecting a DataObject in a Document Document.StreamDescriptionProperty as Stream descriptor. I used that property ages ago probably seen that on some other editor. This PR just change the property

Yes,there's even an editor API for that.

[sdedic]

Seems that all occurrences are replaced.

[sdedic]

Leftover ?
But maybe declare the property as public somewhere to have a shared constant.

[lkishalmi]

Kind of. Did not want to change the API so late in NB16 cycle, so marked that private and made the two now public non API one with a comment. Will pick that up for NB17

[neilcsmith-net]

Great, thanks @lkishalmi . I've seen that exception a couple of times recently testing 16, but could never reproduce what triggered it. Should have opened an issue with it though.