Bug 63769 Endless loop after Show in Package Explorer
there are situations when you run in an endless loop in show in package explorer when the action is attempting to reveal an element.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
private IPartListener fPartListener= new IPartListener() {
		public void partActivated(IWorkbenchPart part) {
			if (part instanceof IEditorPart)
				editorActivated((IEditorPart) part);
		}
		public void partBroughtToTop(IWorkbenchPart part) {
		}
		public void partClosed(IWorkbenchPart part) {
		}
		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 class PackageExplorerProblemTreeViewer extends ProblemTreeViewer {
		boolean fInChangeInput;
		
		public PackageExplorerProblemTreeViewer(Composite parent, int style) {