Bug 25827 Disposing of MemberFilterActionGroup
Build 2.0.2 and 2.1 When investigating an editor memory leak PR we found out that this group has a dispose method which is never called. When we then called from the editor it throw an exeption (viewer was disposed). Don't know if the group really needs dispose() if so it should get called.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/typehierarchy/TypeHierarchyViewPart.java
public void partDeactivated(IWorkbenchPart part) {}
			public void partOpened(IWorkbenchPart part) {}
		};
		
		fSelectionChangedListener= new ISelectionChangedListener() {
			public void selectionChanged(SelectionChangedEvent event) {
				doSelectionChanged(event);
			}
		};
		
	}
	/**
	 * Method doPropertyChange.
	 * @param event
	 */
	private void doPropertyChange(PropertyChangeEvent event) {
		if (fMethodsViewer != null) {
			if (MembersOrderPreferencePage.PREF_OUTLINE_SORT_OPTION.equals(event.getProperty())) {
				fMethodsViewer.refresh();
			}
		}
	}
	
		
	/**
	 * Adds the entry if new. Inserted at the beginning of the history entries list.
	 */		
	private void addHistoryEntry(IJavaElement entry) {
		if (fInputHistory.contains(entry)) {
			fInputHistory.remove(entry);