message: Add TypeScript to Kokoro for web for testing.
  This preps for an upcoming regression test that ensures our TypeScript
  annotations are valid.
diff: @@ -10,6 +10,14 @@ export PATH="$PWD:$PATH"
  python3 --version
  pip3 install mistletoe pygments jsbeautifier future_fstrings
  +# Install a typescript compiler to allow testing.
  +npm install typescript
  +echo "Node Version: "
  +node --version
  +echo "TypeScript Version: "
  +npx tsc --version
  +
  +# Install a specific version of emscripen to avoid surprises.
  curl -L https://github.com/juj/emsdk/archive/0d8576c.zip > emsdk.zip
  unzip emsdk.zip
  mv emsdk-* emsdk
  