Bug 81426 Package Explorer shows nothing after drill into working set, then show projects
I200412160800 - switch Package Explorer to working sets - context menu > Go Into a working set - Show > Projects -> view is empty -> view toolbar button 'Up to Working Sets' does not do anything
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
element2= JavaModelUtil.toOriginal((ICompilationUnit)element2);
    	}
    	return element2;
    }
    private boolean revealAndVerify(Object element) {
    	if (element == null)
    		return false;
    	selectReveal(new StructuredSelection(element));
    	return ! getSite().getSelectionProvider().getSelection().isEmpty();
    }
	public void rootModeChanged(int newMode) {
		fRootMode= newMode;
		if (showWorkingSets() && fWorkingSetModel == null) {
			createWorkingSetModel();
			if (fActionSet != null) {
				fActionSet.getWorkingSetActionGroup().setWorkingSetModel(fWorkingSetModel);
			}
		}
		ISelection selection= fViewer.getSelection();
		Object input= fViewer.getInput();
		boolean isRootInputChange= JavaCore.create(ResourcesPlugin.getWorkspace().getRoot()).equals(input) || (fWorkingSetModel != null && fWorkingSetModel.equals(input));
		try {
			fViewer.getControl().setRedraw(false);
			if (isRootInputChange) {
				fViewer.setInput(null);
			}
			setProviders();
			setSorter();
			fActionSet.getWorkingSetActionGroup().fillFilters(fViewer);
			if (isRootInputChange) {