Major Description
The following exception can occur:
at org.apache.myfaces.view.facelets.util.FaceletsViewDeclarationLanguageUtils.markRenderedResources(FaceletsViewDeclarationLanguageUtils.java:116)
at org.apache.myfaces.view.facelets.FaceletViewDeclarationLanguage.restoreView(FaceletViewDeclarationLanguage.java:2157)
at org.apache.myfaces.application.ViewHandlerImpl.restoreView(ViewHandlerImpl.java:338)
at org.apache.myfaces.lifecycle.RestoreViewExecutor.execute(RestoreViewExecutor.java:168)
at org.apache.myfaces.lifecycle.LifecycleImpl.executePhase(LifecycleImpl.java:195)
at org.apache.myfaces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:142)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:204)
This happens when the view is null, which can happen for a variety of reasons, for example if you drive a request to a page, let the session timeout and then click on a ajaxified button we would get the NPE rather than a ViewExpiredException. The change is trivial I'll upload a patch.