code: function getLaunchStoryboardContentsJSON(splashScreens, launchStoryboardImagesDir) {
  
      var platformLaunchStoryboardImages = mapLaunchStoryboardContents(splashScreens, launchStoryboardImagesDir);
      var contentsJSON = {
          images: [],
          info: {
              author: 'Xcode',
              version: 1
          }
      };
      contentsJSON.images = platformLaunchStoryboardImages.map(function(item) {
          var newItem = {
              idiom: item.idiom,
              scale: item.scale
          };
  
          // Xcode doesn't want any size class property if the class is "any"
          // If our size class is "com", Xcode wants "compact". 
          if (item.width !== CDV_ANY_SIZE_CLASS) {
              newItem['width-class'] = IMAGESET_COMPACT_SIZE_CLASS;
          }
          if (item.height !== CDV_ANY_SIZE_CLASS) {
              newItem['height-class'] = IMAGESET_COMPACT_SIZE_CLASS;
          }
  
          // Xcode doesn't want a filename property if there's no image for these traits       
          if (item.filename) {
              newItem.filename = item.filename;
          }
          return newItem;
      });
      return contentsJSON;
  }
docs: Builds the object that represents the contents.json file for the LaunchStoryboard image set.
  
  The resulting return looks like this:
  
  {
  images: [
  {
  idiom: 'universal|ipad|iphone',
  scale: '1x|2x|3x',
  width-class: undefined|'compact',
  height-class: undefined|'compact'
  }, ...
  ],
  info: {
  author: 'Xcode',
  version: 1
  }
  }
  
  A bit of minor logic is used to map from the array of images returned from mapLaunchStoryboardContents
  to the format requried by Xcode.
  
  @param  {Array<Object>} splashScreens         splash screens as defined in config.xml for this platform
  @param  {string} launchStoryboardImagesDir    project-root/Images.xcassets/LaunchStoryboard.imageset/
  @return {Object}