code: function polymerBuild(config) {
  	const skipRootFolder = function(file) {
  		const rootFolder = config.root || '.';
  		file.dirname = path.relative(rootFolder, file.dirname);
  	};
  
  	const project = new build.PolymerProject(config);
  
  	const bundler = project.bundler({
  		// XXX: sourcemaps makes V8 run out of memory
  		sourcemaps: false,
  		stripComments: true,
  	}).on('error', e => console.error(e));
  
  	return merge(project.sources(), project.dependencies())
  		.pipe(bundler)
  		.pipe(size({title: 'polymer-bundler'}))
  		.pipe(rename(skipRootFolder));
  }
docs: Executes the polymer-build, which a.o. vulcanizes and minifies the HTML
  
  @param {Object} config Content of polymer.json
  @returns