src/core/services/theming/theming.js
function registered(themeName) {
      if (themeName === undefined || themeName === '') return true;
      return applyTheme.THEMES[themeName] !== undefined;
    }
function registered(themeName) {
      if (themeName === undefined || themeName === '') return true;
      return applyTheme.THEMES[themeName] !== undefined;
    }
function registered ( themeName ) { if ( themeName === undefined || themeName === '' ) return true ; return applyTheme . THEMES [ themeName ] !== undefined ; }
Determine is specified theme name is a valid, registered theme
Determine is specified theme name is a valid registered theme