feat: add enhanced gateway features

[yoshi-automation]

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synthtool > You are running the synthesis script directly, this will be disabled in a future release of Synthtool. Please use python3 -m synthtool instead.
synthtool > Ensuring dependencies.
synthtool > Pulling artman image.
latest: Pulling from googleapis/artman
Digest: sha256:2f6b261ee7fe1aedf238991c93a20b3820de37a343d0cacf3e3e9555c2aaf2ea
Status: Image is up to date for googleapis/artman:latest
synthtool > Cloning googleapis.
synthtool > Running generator for google/cloud/iot/artman_cloudiot.yaml.
synthtool > Generated code into /home/kbuilder/.cache/synthtool/googleapis/artman-genfiles/js/iot-v1.
synthtool > Replaced '(listDeviceRegistriesStream\\(.*\n\\s+options = .*\n)(\n\\s+return)' in src/v1/device_manager_client.js.
.circleci/config.yml
.circleci/npm-install-retry.js
.eslintignore
.eslintrc.yml
.github/CONTRIBUTING.md
.github/ISSUE_TEMPLATE/bug_report.md
.github/ISSUE_TEMPLATE/feature_request.md
.github/ISSUE_TEMPLATE/support_request.md
.jsdoc.js
.kokoro/common.cfg
.kokoro/continuous/node10/common.cfg
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.kokoro/continuous/node11/common.cfg
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.kokoro/continuous/node6/common.cfg
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.kokoro/continuous/node8/common.cfg
.kokoro/continuous/node8/docs.cfg
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.kokoro/continuous/node8/samples-test.cfg
.kokoro/continuous/node8/system-test.cfg
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.kokoro/docs.sh
.kokoro/lint.sh
.kokoro/presubmit/node10/common.cfg
.kokoro/presubmit/node10/test.cfg
.kokoro/presubmit/node11/common.cfg
.kokoro/presubmit/node11/test.cfg
.kokoro/presubmit/node6/common.cfg
.kokoro/presubmit/node6/test.cfg
.kokoro/presubmit/node8/common.cfg
.kokoro/presubmit/node8/docs.cfg
.kokoro/presubmit/node8/lint.cfg
.kokoro/presubmit/node8/samples-test.cfg
.kokoro/presubmit/node8/system-test.cfg
.kokoro/presubmit/node8/test.cfg
.kokoro/presubmit/windows/common.cfg
.kokoro/presubmit/windows/test.cfg
.kokoro/samples-test.sh
.kokoro/system-test.sh
.kokoro/test.bat
.kokoro/test.sh
.kokoro/trampoline.sh
.nycrc
CODE_OF_CONDUCT.md
codecov.yaml
npm WARN deprecated [email protected]: no longer maintained
npm WARN deprecated [email protected]: CircularJSON is in maintenance only, flatted is its successor.

> [email protected] install /tmpfs/src/git/autosynth/working_repo/node_modules/grpc
> node-pre-gyp install --fallback-to-build --library=static_library

node-pre-gyp WARN Using request for node-pre-gyp https download 
[grpc] Success: "/tmpfs/src/git/autosynth/working_repo/node_modules/grpc/src/node/extension_binary/node-v57-linux-x64-glibc/grpc_node.node" is installed via remote

> [email protected] postinstall /tmpfs/src/git/autosynth/working_repo/node_modules/protobufjs
> node scripts/postinstall

npm notice created a lockfile as package-lock.json. You should commit this file.
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: [email protected] (node_modules/fsevents):
npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for [email protected]: wanted {"os":"darwin","arch":"any"} (current: {"os":"linux","arch":"x64"})

added 1141 packages from 1274 contributors and audited 4393 packages in 21.411s
found 0 vulnerabilities


> @google-cloud/[email protected] fix /tmpfs/src/git/autosynth/working_repo
> eslint --fix '**/*.js'

synthtool > Cleaned up 2 temporary directories.