title: How do I enable source map generation when using "webdev build"?
body: <p>When using Dart 2 and the <code>webdev build</code> command, I get a <code>build/main.dart.js</code> file. At the end of this file, there is a comment pointing the source map:</p>
  
  <p><code>//# sourceMappingURL=main.dart.js.map</code></p>
  
  <p>However, this file doesn't exist. How do I get the .map file and Dart source files to show up in the build directory so that Chrome devtools will see them?</p>