fix crash of wds when trying to follow emacs lock files by ignoring them in file watcher.

closes facebook#9056

Author: zalox

packages/react-dev-utils/ignoredFiles.js

@@ -11,10 +11,15 @@ const path = require('path');
 const escape = require('escape-string-regexp');
 
 module.exports = function ignoredFiles(appSrc) {
-  return new RegExp(
-    `^(?!${escape(
-      path.normalize(appSrc + '/').replace(/[\\]+/g, '/')
-    )}).+/node_modules/`,
-    'g'
-  );
+  return [
+    new RegExp(
+      `^(?!${escape(
+        path.normalize(appSrc + '/').replace(/[\\]+/g, '/'),
+      )}).+/node_modules/`,
+      'g',
+    ),
+    '**/.#*',
+    '**/*~',
+    '**/#*#',
+  ];
 };