Typescriptify the main process code (5/N)

Summary: Use dev bundling for "yarn start"

Reviewed By: jknoxville

Differential Revision: D20034300

fbshipit-source-id: a46c75074c969f5a4958f498c5c0e15aab808552

scripts/build-release.js

@@ -169,7 +169,7 @@ function downloadIcons(buildFolder) {
   const dir = await buildFolder();
   // eslint-disable-next-line no-console
   console.log('Created build directory', dir);
-  await compileMain();
+  await compileMain({dev: false});
   copyStaticFolder(dir);
   await downloadIcons(dir);
   await compileDefaultPlugins(path.join(dir, 'defaultPlugins'));