Bug 31214 [Show in] Fails for Package Explorer in non-Java project
- create a simple project P - create a simple file called "x.java" in P - open it with the Default Text Editor - in the editor activate "Show in" and select Package Explorer as target -> nothing happens even if P and "x.java" are visible in the Package Explorer
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
if (fMemento != null) {
			restoreLinkingEnabled(fMemento);
		}
		
		makeActions(); 
		
		
		restoreFilterAndSorter();
		fViewer.setInput(findInputElement());
		initDragAndDrop();
		initKeyListener();
			
		fSelectionListener= new ISelectionChangedListener() {
			public void selectionChanged(SelectionChangedEvent event) {
				handleSelectionChanged(event);
			}
		};
		fViewer.addSelectionChangedListener(fSelectionListener);
		
		fViewer.addDoubleClickListener(new IDoubleClickListener() {
			public void doubleClick(DoubleClickEvent event) {
				fActionSet.handleDoubleClick(event);
			}
		});
		
		fViewer.addOpenListener(new IOpenListener() {
			public void open(OpenEvent event) {
				fActionSet.handleOpen(event);
			}
		});