Bug 100429 dropping on type hierarchy method viewer updates input
20050616-0010 - Open a element in the type hierarchy - enable 'Show all inherited methods' - select a method from Object, drop it to itself - Hierarchy of Object is built Drop to itself can happen easely when clicking quickly on entries. Dropping on the method viewer should be disabled (and I think it was before)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/typehierarchy/TypeHierarchyViewPart.java
* @param event
	 */
	protected void doPropertyChange(PropertyChangeEvent event) {
		String property= event.getProperty();
		if (fMethodsViewer != null) {
			if (MembersOrderPreferenceCache.isMemberOrderProperty(event.getProperty())) {
				fMethodsViewer.refresh();
			}
		}
		if (IWorkingSetManager.CHANGE_WORKING_SET_CONTENT_CHANGE.equals(property)) {
			updateHierarchyViewer(true);
			updateTitle();
		}
	}
		
	/**
	 * Adds the entry if new. Inserted at the beginning of the history entries list.
	 * @param entry The new entry
	 */		
	private void addHistoryEntry(IJavaElement entry) {
		if (fInputHistory.contains(entry)) {
			fInputHistory.remove(entry);
		}
		fInputHistory.add(0, entry);
		fHistoryDropDownAction.setEnabled(true);
	}
	
	private void updateHistoryEntries() {
		for (int i= fInputHistory.size() - 1; i >= 0; i--) {
			IJavaElement type= (IJavaElement) fInputHistory.get(i);