Bug 15301 'show in packages view' - does not work fo java files not in source folders
20020502 open a java file that is in a resource folder (so it is not an ICompilationUnit - just a file with .java extension) 'show in packages view' is present in the context menu but it does nothing
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
static final String TAG_SHOWLIBRARIES = "showLibraries"; 
	static final String TAG_SHOWBINARIES = "showBinaries"; 
	private JavaElementPatternFilter fPatternFilter= new JavaElementPatternFilter();
	private LibraryFilter fLibraryFilter= new LibraryFilter();
	private PackageExplorerActionGroup fActionSet;
	private ProblemTreeViewer fViewer; 
	private Menu fContextMenu;		
	
	private IMemento fMemento;	
	private ISelectionChangedListener fSelectionListener;
	
	private String fWorkingSetName;
	
	
	private IPartListener fPartListener= new IPartListener() {
		public void partActivated(IWorkbenchPart part) {
			if (part instanceof IEditorPart)
				editorActivated((IEditorPart) part);
		}
		public void partBroughtToTop(IWorkbenchPart part) {
		}
		public void partClosed(IWorkbenchPart part) {
		}
		public void partDeactivated(IWorkbenchPart part) {
		}
		public void partOpened(IWorkbenchPart part) {
		}
	};
	
	private ITreeViewerListener fExpansionListener= new ITreeViewerListener() {