we don't need to access files in device directory and distribution directory twice, it would be better to merge two `if` to one `if/else if` like:
```js
HomescreenAppBuilder.prototype.customizeHomescreen = function() {
  var configPath;
  var distributionCustom
  ...(ignore)
  if (config.GAIA_DISTRIBUTION_DIR) {
    configPath = config.GAIA_DISTRIBUTION_DIR;
  } else if (config.GAIA_DEVICE_TYPE) {
    configPath = config.configPath;
  }
  distributionCustom =
    JSON.parse(utils.getDistributionFileContent('homescreens',
      customize, configPath));
  customize = this.customizeSettings(customize, distributionCustom);
}
```