Revert of Remove SIMD.js from V8.

test/simdjs/simdjs.isolate

Index: test/simdjs/simdjs.isolate
diff --git a/test/simdjs/simdjs.isolate b/test/simdjs/simdjs.isolate
new file mode 100644
index 0000000000000000000000000000000000000000..dbeca5e55cfc8b0ddcae07ee4af4a80f22ccdd0a
--- /dev/null
+++ b/test/simdjs/simdjs.isolate
@@ -0,0 +1,14 @@
+# 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.
+{
+  'variables': {
+    'files': [
+      './',
+    ],
+  },
+  'includes': [
+    '../../src/d8.isolate',
+    '../../tools/testrunner/testrunner.isolate',
+  ],
+}