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/packageview/PackageExplorerActionGroup.java
}
	 void handleSelectionChanged(SelectionChangedEvent event) {
		fZoomInAction.update();
	}
	
	public void fillContextMenu(IMenuManager menu) {		
		IStructuredSelection selection= (IStructuredSelection)getContext().getSelection();
		int size= selection.size();
		Object element= selection.getFirstElement();
		
		addGotoMenu(menu, element, size);
		
		addOpenNewWindowAction(menu, element);
		
		super.fillContextMenu(menu);
	}
	
	 private void addGotoMenu(IMenuManager menu, Object element, int size) {
		
		if (size == 1 && fPart.getViewer().isExpandable(element) && (isGoIntoTarget(element) || element instanceof IContainer))
			menu.appendToGroup(IContextMenuConstants.GROUP_GOTO, fZoomInAction);
	}
	
	private boolean isNewTarget(IJavaElement element) {
		if (element == null)
			return false;
		int type= element.getElementType();
		return type == IJavaElement.JAVA_PROJECT ||
			type == IJavaElement.PACKAGE_FRAGMENT_ROOT || 
			type == IJavaElement.PACKAGE_FRAGMENT ||