[Intl] Add test cases for %%ALIAS locales

Bug: v8:9312, chromium:968269
Change-Id: I0e3d134cd4341c30277df62fead6386e344be0bf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1636179
Commit-Queue: Frank Tang <ftang@chromium.org>
Reviewed-by: Mathias Bynens <mathias@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61952}

test/intl/intl.status

@@ -34,6 +34,9 @@
   'collator/check-kf-option': [FAIL],
   'collator/check-kn-option': [FAIL],
 
+  # https://code.google.com/p/v8/issues/detail?id=9312
+  'regress-9312': [FAIL],
+
   # Slow tests.
   'regress-903566': [PASS, SLOW],
 }],  # ALWAYS

test/intl/regress-9312.js

+// Copyright 2019 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.
+
+// Test the locales in src/third_party/icu/source/data/locales/ which
+// has %%ALIAS output the same as what it alias to instead of root.
+const aliases = new Map([
+  ['sh', 'sr-Latn'],
+  ['in', 'id'],
+  ['mo', 'ro'],
+  ['iw', 'he'],
+  ['no', 'nb'],
+  ['tl', 'fil'],
+  ['iw-IL', 'he-IL'],
+  ['sr-CS', 'sr-Cyrl-RS'],
+]);
+
+const date = new Date();
+const number = 123456789.123456789;
+for (const [from, to] of aliases) {
+  const fromDTF = new Intl.DateTimeFormat(from, {month: 'long', weekday: 'long'});
+  const toDTF = new Intl.DateTimeFormat(to, {month: 'long', weekday: 'long'});
+  for (let m = 0; m < 12; m++) {
+    date.setMonth(m);
+    assertEquals(fromDTF.format(date), toDTF.format(date),
+        `Expected to see the same output from "${from}" and "${to}".`);
+  }
+  const fromNF = new Intl.NumberFormat(from);
+  const toNF = new Intl.NumberFormat(to);
+  assertEquals(fromNF.format(number), toNF.format(number),
+      `Expected to see the same output from "${from}" and "${to}".`);
+}