Bug 52474 UI Blocked when opening Java Perspective during CVS check out
build I20040218 - start eclipse with a new workspace - switch to CVS Repository Exploring perspective - check out a number of projects ( i checkout Platform UI module) - now attempt to switch to the Java Perspective NOTE that at this point the "UI is blocked" dialog is opened. Probably due to the fact that starting the Java Perspective requires the workbench lock? The point here is that this will be a common pattern and it would be nice if we could investigate makeing this scenario work more smoothly.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
public void partDeactivated(IWorkbenchPart part) {
		}
		public void partOpened(IWorkbenchPart part) {
		}
	};
	
	private ITreeViewerListener fExpansionListener= new ITreeViewerListener() {
		public void treeCollapsed(TreeExpansionEvent event) {
		}
		
		public void treeExpanded(TreeExpansionEvent event) {
			Object element= event.getElement();
			if (element instanceof ICompilationUnit || 
				element instanceof IClassFile)
				expandMainType(element);
		}
	};
	private PackageExplorerLabelProvider fLabelProvider;	
	
	/* (non-Javadoc)
	 * Method declared on IViewPart.
	 */
	private boolean fLinkingEnabled;
    public void init(IViewSite site, IMemento memento) throws PartInitException {
		super.init(site, memento);
		fMemento= memento;
		restoreLayoutState(memento);
	}
	private void restoreLayoutState(IMemento memento) {
		Integer state= null;