Prevent closed Menu from being selectable

[CumpsD]

When a menu is closed, the opacity is set to 0. The height is set to 0 as well. However, due to padding top and bottom being 8, there as a 16px high invisible section present on the screen, which was selectable (the first menu item would get clicked)

To fix this, we need to remove the padding if it is in closed mode.

[CumpsD]

For information, right now I solved this without changing material-ui code by doing:

    componentDidMount() {
        this._fixMenuVisibilityBug();
    }

    componentDidUpdate() {
        this._fixMenuVisibilityBug();
    }

    _fixMenuVisibilityBug() {
        var avatarMenuVisible = this.props.avatarMenuVisible;
        log('Fixing up avatar menu visibility bug.', avatarMenuVisible);
        var el = React.findDOMNode(this.refs.avatarMenu);
        if (avatarMenuVisible) {
            el.style.paddingTop = Spacing.desktopGutterMini + 'px';
            el.style.paddingBottom = Spacing.desktopGutterMini + 'px';
        } else {
            el.style.paddingTop = '0px';
            el.style.paddingBottom = '0px';
        }
    }

[hai-cea]

Thanks @CumpsD !