Bug 11773 java browsing: sorter for Members view
i'd like to be able to sort and filters things in package and type views (sorting more important)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/browsing/MembersView.java
*/
	protected String getHelpContextId() {
		return IJavaHelpContextIds.MEMBERS_VIEW;
	}
	/**
	 * Creates the the viewer of this part.
	 * 
	 * @param parent	the parent for the viewer
	 */
	protected StructuredViewer createViewer(Composite parent) {
		ProblemTreeViewer viewer= new ProblemTreeViewer(parent, SWT.MULTI);
		fMemberFilterActionGroup= new MemberFilterActionGroup(viewer, JavaPlugin.ID_PACKAGES_VIEW);
		return viewer;
	}
	/**
	 * Adds filters the viewer of this part.
	 */
	protected void addFilters() {
	}
	protected void fillToolBar(IToolBarManager tbm) {
		fMemberFilterActionGroup.contributeToToolBar(tbm);
	}
	
	/**
	 * Answers if the given <code>element</code> is a valid
	 * input for this part.
	 * 
	 * @param 	element	the object to test
	 * @return	<true> if the given element is a valid input
	 */