[regexp] Fix a test case for RE.proto[@@search]

[regexp] Fix a test case for RE.proto[@@search]

The test case did not test anything in its original form. Fix it and add
documentation.

BUG=v8:5339
Committed: https://crrev.com/f354558c8030c41e99413f7f7ee4c0aa9bcc60ac
Cr-Commit-Position: refs/heads/master@{#40794}

[jgruber, 2016-11-07 08:07:45]

The CQ bit was checked by jgruber@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-11-07 08:07:47]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[jgruber, 2016-11-07 08:10:01]

jgruber@chromium.org changed reviewers:
+ littledan@chromium.org, yangguo@chromium.org

[jgruber, 2016-11-07 08:10:01]

This fixes an issue found by littledan@ in
https://codereview.chromium.org/2452923002/.

[commit-bot: I haz the power, 2016-11-07 08:31:17]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-11-07 08:31:17]

Dry run: This issue passed the CQ dry run.

[Yang, 2016-11-07 09:27:51]

On 2016/11/07 08:10:01, jgruber wrote:
> This fixes an issue found by littledan@ in
> https://codereview.chromium.org/2452923002/.

lgtm.

[jgruber, 2016-11-07 09:49:14]

The CQ bit was checked by jgruber@chromium.org

[commit-bot: I haz the power, 2016-11-07 09:49:23]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-07 09:51:18]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-11-17 22:24:16]

Description was changed from

==========
[regexp] Fix a test case for RE.proto[@@search]

The test case did not test anything in its original form. Fix it and add
documentation.

BUG=v8:5339
==========

to

==========
[regexp] Fix a test case for RE.proto[@@search]

The test case did not test anything in its original form. Fix it and add
documentation.

BUG=v8:5339

Committed: https://crrev.com/f354558c8030c41e99413f7f7ee4c0aa9bcc60ac
Cr-Commit-Position: refs/heads/master@{#40794}
==========

[commit-bot: I haz the power, 2016-11-17 22:24:17]

Patchset 1 (id:??) landed as
https://crrev.com/f354558c8030c41e99413f7f7ee4c0aa9bcc60ac
Cr-Commit-Position: refs/heads/master@{#40794}