Add 'browser' and 'module' package main fields

This is required for some 3rd party dependencies to work.

Author: pmoleri

packages/react-scripts/config/webpack.config.js

@@ -62,7 +62,12 @@ module.exports = function(webpackEnv) {
   const isEnvDevelopment = webpackEnv === 'development';
   const isEnvProduction = webpackEnv === 'production';
 
-  const workspacesMainFields = [workspacesConfig.packageEntry, 'main'];
+  const workspacesMainFields = [
+    workspacesConfig.packageEntry,
+    'browser',
+    'module',
+    'main',
+  ];
   const mainFields =
     isEnvDevelopment && workspacesConfig.development
       ? workspacesMainFields