A java.lang.AssertionError exception has occurred when editing xhtml files

### Apache NetBeans version

Apache NetBeans latest daily build

### What happened

A java.lang.AssertionError exception has occurred when i pressed CTRL+SPACE for code completion in xhtml files

### How to reproduce

- open xhtml for editing
- press CTRL+SPACE to select th appropriate JSF ManagedBean
- the autosuggestion list appear correctly but a java.lang.AssertionError exception has occurred


### Did this work correctly in an earlier version?

Apache NetBeans 13

### Operating System

Windows 10 64 bits

### JDK

Eclipse Adoptium / jdk-17.0.2.8-hotspot

### Apache NetBeans packaging

Apache NetBeans provided installer

### Anything else

- NetBeans IDE 14-rc1
- Eclipse Adoptium / jdk-17.0.2.8-hotspot
- Windows 10 64bits
- A Joinfaces (JSF + Spring Boot) Maven Project
- NB-SpringBoot Plugin installed : Version 3.0 (Oct 2019)
- StackTrace :

```
java.lang.AssertionError
at com.sun.tools.javac.util.Assert.error(Assert.java:155)
at com.sun.tools.javac.util.Assert.checkNonNull(Assert.java:62)
at com.sun.tools.javac.comp.Modules.allModules(Modules.java:1216)
at com.sun.tools.javac.model.JavacElements.getAllModuleElements(JavacElements.java:127)
at org.netbeans.modules.java.source.ElementUtils.getTypeElementByBinaryName(ElementUtils.java:49)
at org.netbeans.api.java.source.ElementHandle.getTypeElementByBinaryName(ElementHandle.java:663)
at org.netbeans.api.java.source.ElementHandle.resolveImpl(ElementHandle.java:162)
at org.netbeans.api.java.source.ElementHandle.resolve(ElementHandle.java:131)
at org.netbeans.modules.web.el.completion.ELJavaCompletionItem$ElementHandleAdapter$1.run(ELJavaCompletionItem.java:315)
at org.netbeans.modules.web.el.completion.ELJavaCompletionItem$ElementHandleAdapter$1.run(ELJavaCompletionItem.java:311)
at org.netbeans.modules.java.source.parsing.MimeTask.run(MimeTask.java:60)
at org.netbeans.modules.parsing.impl.TaskProcessor.callUserTask(TaskProcessor.java:586)
at org.netbeans.modules.parsing.api.ParserManager$MimeTaskAction.run(ParserManager.java:364)
at org.netbeans.modules.parsing.api.ParserManager$MimeTaskAction.run(ParserManager.java:347)
at org.netbeans.modules.parsing.impl.TaskProcessor$2.call(TaskProcessor.java:181)
at org.netbeans.modules.parsing.impl.TaskProcessor$2.call(TaskProcessor.java:178)
at org.netbeans.modules.masterfs.filebasedfs.utils.FileChangedManager.priorityIO(FileChangedManager.java:153)
at org.netbeans.modules.masterfs.providers.ProvidedExtensions.priorityIO(ProvidedExtensions.java:335)
at org.netbeans.modules.parsing.nb.DataObjectEnvFactory.runPriorityIO(DataObjectEnvFactory.java:118)
at org.netbeans.modules.parsing.impl.Utilities.runPriorityIO(Utilities.java:67)
at org.netbeans.modules.parsing.impl.TaskProcessor.runUserTask(TaskProcessor.java:178)
at org.netbeans.modules.parsing.api.ParserManager.parse(ParserManager.java:318)
at org.netbeans.api.java.source.JavaSource.runUserActionTaskImpl(JavaSource.java:433)
at org.netbeans.api.java.source.JavaSource.runUserActionTask(JavaSource.java:425)
at org.netbeans.modules.web.el.completion.ELJavaCompletionItem$ElementHandleAdapter.document(ELJavaCompletionItem.java:311)
at org.netbeans.modules.web.el.completion.ELCodeCompletionHandler.documentElement(ELCodeCompletionHandler.java:729)
at org.netbeans.modules.csl.editor.completion.GsfCompletionDoc.(GsfCompletionDoc.java:91)
at org.netbeans.modules.csl.editor.completion.GsfCompletionDoc.create(GsfCompletionDoc.java:108)
at org.netbeans.modules.csl.editor.completion.GsfCompletionProvider$JavaCompletionQuery.resolveDocumentation(GsfCompletionProvider.java:528)
at org.netbeans.modules.csl.editor.completion.GsfCompletionProvider$JavaCompletionQuery$1.run(GsfCompletionProvider.java:315)
at org.netbeans.modules.parsing.impl.TaskProcessor.callUserTask(TaskProcessor.java:586)
at org.netbeans.modules.parsing.api.ParserManager$UserTaskAction.run(ParserManager.java:132)
at org.netbeans.modules.parsing.api.ParserManager$UserTaskAction.run(ParserManager.java:116)
at org.netbeans.modules.parsing.impl.TaskProcessor$2.call(TaskProcessor.java:181)
at org.netbeans.modules.parsing.impl.TaskProcessor$2.call(TaskProcessor.java:178)
at org.netbeans.modules.masterfs.filebasedfs.utils.FileChangedManager.priorityIO(FileChangedManager.java:153)
at org.netbeans.modules.masterfs.providers.ProvidedExtensions.priorityIO(ProvidedExtensions.java:335)
at org.netbeans.modules.parsing.nb.DataObjectEnvFactory.runPriorityIO(DataObjectEnvFactory.java:118)
at org.netbeans.modules.parsing.impl.Utilities.runPriorityIO(Utilities.java:67)
at org.netbeans.modules.parsing.impl.TaskProcessor.runUserTask(TaskProcessor.java:178)
at org.netbeans.modules.parsing.api.ParserManager.parse(ParserManager.java:83)
at org.netbeans.modules.csl.editor.completion.GsfCompletionProvider$JavaCompletionQuery.query(GsfCompletionProvider.java:320)
at org.netbeans.spi.editor.completion.support.AsyncCompletionTask.run(AsyncCompletionTask.java:198)
at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1418)
at org.netbeans.modules.openide.util.GlobalLookup.execute(GlobalLookup.java:45)
at org.openide.util.lookup.Lookups.executeWith(Lookups.java:278)
[catch] at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2033)

```

### Are you willing to submit a pull request?

No

### Code of Conduct

Yes

Start with org.netbeans.modules.web.el.completion.ELCodeCompletionHandler.documentElement and ELJavaCompletionItem, then follow the ElementHandle and ElementUtils calls shown in the stack trace. Reproduce CTRL+SPACE in an XHTML file and investigate the Java module assertion; done means completion no longer raises java.lang.AssertionError and its documentation can be displayed.

Written by the indexing model from the issue text.