function UserSheetController( $mdBottomSheet ) {
      this.user = user;
      this.items = [
        { name: 'Phone'       , icon: 'phone'       , icon_url: 'assets/svg/phone.svg'},
        { name: 'Twitter'     , icon: 'twitter'     , icon_url: 'assets/svg/twitter.svg'},
        { name: 'Google+'     , icon: 'google_plus' , icon_url: 'assets/svg/google_plus.svg'},
        { name: 'Hangout'     , icon: 'hangouts'    , icon_url: 'assets/svg/hangouts.svg'}
      ];
      this.performAction = (action) => {
        $mdBottomSheet.hide(action);
      };
    }
Bottom Sheet controller for the Avatar Actions