Install emscripten https://emscripten.org/docs/getting_started/index.html

  git clone https://github.com/emscripten-core/emsdk.git
  cd emsdk
  ./emsdk install 1.38.33
  ./emsdk activate 1.38.33
  source ./emsdk_env.sh

Install piexwasm project components

  cd chrome/src/ui/file_manager/image_loader/piex
  npm install

Build piexwasm code: piex.js.wasm piex.out.wasm

  npm run build

Run tests: they must PASS

  npm run test

Release: submit piex.js.wasm piex.out.wasm to the Chromium repository

  git commit -a -m "Release piexwasm at emscripten <version> ..."
  git cl upload

Release Builder: emscripten 1.38.33