message: refactor(docs-infra): simplify regex in search WebWorker
  This commit simplifies a regex used in angular.io's search WebWorker. It
  also updates some comments to add more context on what the code does.
  PR Close
diff: @@ -119,7 +119,8 @@ function queryIndex(query: string): PageInfo[] {
  try {
  if (query.length) {
  // First try a query where every term must be present
  - const queryAll = query.replace(/(^|\s)([^\s]+)/g, '$1+$2');
  + // (see https://lunrjs.com/guides/searching.html#term-presence)
  + const queryAll = query.replace(/\S+/g, '+$&');
  let results = index.search(queryAll);
  // If that was too restrictive just query for any term to be present
  @@ -129,7 +130,7 @@ function queryIndex(query: string): PageInfo[] {
  // If that is still too restrictive then search in the title for the first word in the query
  if (results.length === 0) {
  - // E.g. if the search is "ngCont guide" then we search for "ngCont guide title:ngCont*"
  + // E.g. if the search is "ngCont guide" then we search for "ngCont guide title:*ngCont*"
  const titleQuery = 'title:*' + query.split(' ', 1)[0] + '*';
  results = index.search(query + ' ' + titleQuery);
  }
  