[js-perf-test] Add RegExp microbenchmarks

test/js-perf-test/RegExp/slow_replace.js

Index: test/js-perf-test/RegExp/slow_replace.js
diff --git a/test/js-perf-test/RegExp/slow_replace.js b/test/js-perf-test/RegExp/slow_replace.js
new file mode 100644
index 0000000000000000000000000000000000000000..c0726175f18509abd90aeea0e39f7d1c185617b8
--- /dev/null
+++ b/test/js-perf-test/RegExp/slow_replace.js
@@ -0,0 +1,8 @@
+// Copyright 2016 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.
+
+load("base.js");
+load("base_replace.js");
+
+createSlowBenchmarkSuite("Replace");