Bug 64880 Wrong rendering of unbound User library in package explorer [package explorer]
RC1 - create a user library for JUnit - now edit the .classpath file so that the class path entry points to a non existing library (e.g. <classpathentry kind="con" path="org.eclipse.jdt.USER_LIBRARY/JUnit2"/>) - save - the package explorer contain two JRE entries.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/ClassPathContainer.java
this.fProject= project;
		}
		
		public IJavaElement getProject() {
			return fProject; 
		}
		
		public Object getAdapter(Class adapter) {
			if (adapter == IWorkbenchAdapter.class) 
				return this;
			return null;
		}
		public Object[] getChildren(Object o) {
			return null;
		}
		public ImageDescriptor getImageDescriptor(Object object) {
			return DESC_OBJ_PROJECT;
		}
		public String getLabel(Object o) {
			return fProject.getElementName();
		}
		public Object getParent(Object o) {
			return null;
		}
	}
	public ClassPathContainer(IJavaProject parent, IClasspathEntry entry) {
		fProject= parent;
		fClassPathEntry= entry;
		try {
			fContainer= JavaCore.getClasspathContainer(entry.getPath(), parent);