Remove regress-crbug-518748. It's too hard to make this non-flaky

test/mjsunit/regress/regress-crbug-518748.js

Index: test/mjsunit/regress/regress-crbug-518748.js
diff --git a/test/mjsunit/regress/regress-crbug-518748.js b/test/mjsunit/regress/regress-crbug-518748.js
deleted file mode 100644
index cccbc26c245e8b9cc227b9b62d66ddd5bb6c6b50..0000000000000000000000000000000000000000
--- a/test/mjsunit/regress/regress-crbug-518748.js
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2015 the V8 project authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-if (this.Worker) {
-  var workersToCreate = 1000;
-  var workers = [];
-  assertThrows(function() {
-    for (var i = 0; i < workersToCreate; i++) {
-      workers.push(new Worker(''));
-    }
-  });
-  print('#workers: ', workers.length);
-}