Revert of [date] Add ICU backend for timezone info behind a flag

test/mjsunit/icu-date-lord-howe.js

Index: test/mjsunit/icu-date-lord-howe.js
diff --git a/test/mjsunit/icu-date-lord-howe.js b/test/mjsunit/icu-date-lord-howe.js
deleted file mode 100644
index bf460013d76058a6cbdec4f369ae1c676b0eec97..0000000000000000000000000000000000000000
--- a/test/mjsunit/icu-date-lord-howe.js
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2017 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.
-
-// Flags: --icu-timezone-data
-// Environment Variables: TZ=Australia/Lord_Howe LC_ALL=en
-
-assertEquals(
-   "Mon Jan 01 1990 11:00:00 GMT+1100 (Lord Howe Daylight Time)",
-   new Date("1990-01-01").toString());
-
-assertEquals(
-   "Fri Jun 01 1990 10:30:00 GMT+1030 (Lord Howe Standard Time)",
-   new Date("1990-06-01").toString());