message: ci: run 'yarn install' for doc_test task
diff: @@ -40,7 +40,7 @@ if [[ ${TRAVIS} && (${CI_MODE} == "e2e" || ${CI_MODE} == "aio" || ${CI_MODE} ==
  fi
  -if [[ ${TRAVIS} && ${CI_MODE} == "aio" ]]; then
  +if [[ ${TRAVIS} && (${CI_MODE} == "aio" || ${CI_MODE} == "docs_test") ]]; then
  # angular.io: Install all yarn dependencies according to angular.io/yarn.lock
  echo 'travis_fold:start:install.aio.node_modules'
  cd "`dirname $0`/../../aio"
  