message: build(aio): don't render `@Annotation` tags
  Because we were "ignoring" these tags they were being
  rendered as part of the previous tag.
  What we really want to do is know about them, so that we
  don't break the doc-gen but then ignore them when rendering.
  PR Close
diff: -// A ts2dart compiler annotation that can be ignored in API docs.
  +// A ts2dart compiler annotation that we don't care about for API docs.
  +// But, if we don't have a tag-def for it the doc-gen will error.
  module.exports = function() {
  - return {name: 'Annotation', ignore: true};
  + return {name: 'Annotation'};
  };
  