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
/**
	 * Determines the input element to be used initially .
	 */	
	private IJavaElement determineInputElement() {
		Object input= getSite().getPage().getInput();
		if (input instanceof IJavaElement) { 
			IJavaElement elem= (IJavaElement) input;
			if (elem instanceof IMember) {
				return elem;
			} else {
				int kind= elem.getElementType();
				if (kind == IJavaElement.JAVA_PROJECT || kind == IJavaElement.PACKAGE_FRAGMENT_ROOT || kind == IJavaElement.PACKAGE_FRAGMENT) {
					return elem;
				}
			}
		} 
		return null;	
	}
	
	/*
	 * @see IViewPart#init
	 */
	public void init(IViewSite site, IMemento memento) throws PartInitException {
		super.init(site, memento);
		fMemento= memento;
	}	
	
	/*
	 * @see ViewPart#saveState(IMemento)
	 */