Bug 11770 java browsing: multi-selection disabled in 2 of 4 views
multi selection is disabled in the package and type views but it's enabled in project and member views
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/browsing/JavaBrowsingPart.java
if (newInput == null)
			return part == fPreviousSelectionProvider;
			
		if (input instanceof IJavaElement && newInput instanceof IJavaElement)
			return getTypeComparator().compare(newInput, input)  > 0;
		else
			return false;
	}
	protected boolean isAncestorOf(Object ancestor, Object element) {
		if (element instanceof IJavaElement && ancestor instanceof IJavaElement)
			return !element.equals(ancestor) && internalIsAncestorOf((IJavaElement)ancestor, (IJavaElement)element);
		return false;
	}
	
	private boolean internalIsAncestorOf(IJavaElement ancestor, IJavaElement element) {
		if (element != null)
			return element.equals(ancestor) || internalIsAncestorOf(ancestor, element.getParent());
		else
			return false;
	}
	public void selectionChanged(IWorkbenchPart part, ISelection selection) {
		
		if (!fProcessSelectionEvents || part == this || !(selection instanceof IStructuredSelection))
			return;
			
		if (selection.isEmpty() && part instanceof JavaBrowsingPart && !(part instanceof ProjectsView))
			return;
		
		
		Object newInput= getElementFromSingleSelection(selection);