Bug 4373 Packages View - double clich doesn't expand two hiearchy levels
- enable: Show CU children in packages view - double click on CU observe: only one level gets expanded - now expand a node by clicking on the + observe: two levels get expanded
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
ctrl.getDisplay().asyncExec(new Runnable() {
						public void run() {
							Control ctrl= fViewer.getControl();
							if (ctrl != null && !ctrl.isDisposed()) 
								fViewer.expandToLevel(type2, 1);
						}
					}); 
				}
			}
		} catch(JavaModelException e) {
			
		}
	}
	
	/**
	 * Returns the element contained in the EditorInput
	 */
	Object getElementOfInput(IEditorInput input) {
		if (input instanceof IFileEditorInput)
			return ((IFileEditorInput)input).getFile();
		else if (input instanceof ClassFileEditorInput)
			return ((ClassFileEditorInput)input).getClassFile();
		else if (input instanceof JarEntryEditorInput)
			return ((JarEntryEditorInput)input).getStorage();
		return null;
	}
	
	/**
 	 * Returns the Viewer.
 	 */