Bug 81877 Package explorer forgets active working set [package explorer]
3.1 M4 1. open pkg explorer. 2. select a working set, pkg explorer updates and filters out projects. 3. close pkg explorer. 4. open package explorer again and the working set is no longer applied. This used to work.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
}
	private boolean inputIsSelected(IEditorInput input) {
		IStructuredSelection selection= (IStructuredSelection)fViewer.getSelection();
		if (selection.size() != 1) 
			return false;
		IEditorInput selectionAsInput= null;
		try {
			selectionAsInput= EditorUtility.getEditorInput(selection.getFirstElement());
		} catch (JavaModelException e1) {
			return false;
		}
		return input.equals(selectionAsInput);
	}
	boolean showInput(Object input) {
		Object element= null;
			
		if (input instanceof IFile && isOnClassPath((IFile)input)) {
			element= JavaCore.create((IFile)input);
		}
				
		if (element == null) 
			element= input;
				
		if (element != null) {
			ISelection newSelection= new StructuredSelection(element);
			if (fViewer.getSelection().equals(newSelection)) {
				fViewer.reveal(element);
			} else {
				try {
					fViewer.removeSelectionChangedListener(fSelectionListener);