Bug 45062 Don't filter output folder and class files
Create a Java project with source folder src and output folder bin. The bin folder will not be shown in the Packages Explorer. Create a Java project with source folder src and output folder output/bin. The output and bin folders are shown in the Packages Explorer. Implictly filtering out bin is confusing and inconsistent. A better way to do this would be to use a name filter for bin or add "Output folder" to the list of available filters.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
fViewer.getTree().setMenu(fContextMenu);
		
		
		IWorkbenchPartSite site= getSite();
		site.registerContextMenu(menuMgr, fViewer);
		site.setSelectionProvider(fViewer);
		site.getPage().addPartListener(fPartListener);
		
		if (fMemento != null) {
			restoreLinkingEnabled(fMemento);
		}
		
		makeActions(); 
		
		
		restoreFilterAndSorter();
		fViewer.setInput(findInputElement());
		initFrameActions();
		initKeyListener();
			
		fSelectionListener= new ISelectionChangedListener() {
			public void selectionChanged(SelectionChangedEvent event) {
				handleSelectionChanged(event);
			}
		};
		fViewer.addPostSelectionChangedListener(fSelectionListener);
		
		fViewer.addDoubleClickListener(new IDoubleClickListener() {
			public void doubleClick(DoubleClickEvent event) {
				fActionSet.handleDoubleClick(event);