Use optparse in js2c.py for python compatibility

Use optparse in js2c.py for python compatibility

Without this change, V8 won't build on RHEL/CentOS 6 because the distro
python is too old to know about the argparse module.

Can this commit be cherry-picked to the 4.4 branch?  It should apply
cleanly.

BUG=

Committed: https://crrev.com/44bc918458481d60b08d5566f0f31a79e39b85d7
Cr-Commit-Position: refs/heads/master@{#29186}

[bnoordhuis, 2015-06-19 20:51:18]

ben@strongloop.com changed reviewers:
+ domenic@chromium.org, machenbach@chromium.org

[domenic, 2015-06-19 21:01:40]

The reason we switched to argparse is because optparse doesn't allow nargs="*"
options (see
https://github.com/v8/v8-git-mirror/commit/8a89a4a5ceeb58303cd9bc2d3e8d362742...).
However, as of
https://github.com/v8/v8-git-mirror/commit/c93aff4ac63ad9ffb6318e750335208de3...
we no longer need that feature, so this should be OK, at least until next time
we need such functionality.

I'll let others comment on whether supporting outdated Python versions is a goal
for V8 or whether depot_tools is the blessed path.

[noordhuis, 2015-06-19 21:14:22]

For background: https://github.com/nodejs/io.js/pull/2022

I realize compatibility with older systems isn't a big issue for Google, but it
is for io.js and node.js.

[Michael Achenbach, 2015-06-22 07:09:24]

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

[commit-bot: I haz the power, 2015-06-22 07:09:30]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1192973004/1

[Michael Achenbach, 2015-06-22 07:10:07]

machenbach@chromium.org changed reviewers:
+ yangguo@chromium.org

[Michael Achenbach, 2015-06-22 07:10:08]

lgtm

+yang

[Yang, 2015-06-22 07:23:31]

On 2015/06/22 07:10:08, Michael Achenbach wrote:
> lgtm
> 
> +yang

lgtm.

[commit-bot: I haz the power, 2015-06-22 07:30:20]

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

[commit-bot: I haz the power, 2015-06-22 07:30:21]

Dry run: This issue passed the CQ dry run.

[bnoordhuis, 2015-06-22 12:05:43]

The CQ bit was checked by ben@strongloop.com

[commit-bot: I haz the power, 2015-06-22 12:05:53]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1192973004/1

[commit-bot: I haz the power, 2015-06-22 12:13:58]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-06-22 12:14:07]

Patchset 1 (id:??) landed as
https://crrev.com/44bc918458481d60b08d5566f0f31a79e39b85d7
Cr-Commit-Position: refs/heads/master@{#29186}