Update test262.

Rolling v8/test/test262/data: https://chromium.googlesource.com/external/github.com/tc39/test262/+log/7e65999..ff8b10c

TBR=adamk@chromium.org,gsathya@chromium.org

Change-Id: I7c7bc6367724498f17ccfabce88b29c2f4595121
Reviewed-on: https://chromium-review.googlesource.com/c/1261876Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#56382}

DEPS

@@ -57,7 +57,7 @@ deps = {
   'v8/test/mozilla/data':
     Var('chromium_url') + '/v8/deps/third_party/mozilla-tests.git' + '@' + 'f6c578a10ea707b1a8ab0b88943fe5115ce2b9be',
   'v8/test/test262/data':
-    Var('chromium_url') + '/external/github.com/tc39/test262.git' + '@' + '7e65999731cb6cd6fab10a92e8b7bd39a6b0793c',
+    Var('chromium_url') + '/external/github.com/tc39/test262.git' + '@' + 'ff8b10c448ab0b884deac4e6e5818ed84ab8ecd9',
   'v8/test/test262/harness':
     Var('chromium_url') + '/external/github.com/test262-utils/test262-harness-py.git' + '@' + '0f2acdd882c84cff43b9d60df7574a1901e2cdcd',
   'v8/third_party/qemu-linux-x64': {