Fix ScopedTempDir in base_unittests

Fix ScopedTempDir in base_unittests

BUG=546640
Committed: https://crrev.com/8fc5ec7879e78806a00e6755e4bd8ab0ffd07df2
Cr-Commit-Position: refs/heads/master@{#355691}

[jschuh, 2015-10-22 22:49:34]

jschuh@chromium.org changed reviewers:
+ thestig@chromium.org

[jschuh, 2015-10-22 22:49:35]

I promise not to send all of these to you.

[Lei Zhang, 2015-10-22 22:53:53]

lgtm

[jschuh, 2015-10-22 23:42:02]

The CQ bit was checked by jschuh@chromium.org

[commit-bot: I haz the power, 2015-10-22 23:42:20]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1415293006/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1415293006/1

[commit-bot: I haz the power, 2015-10-23 00:14:43]

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

[commit-bot: I haz the power, 2015-10-23 00:14:44]

Try jobs failed on following builders:
  cast_shell_linux on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/cast_shell_linu...)
  linux_chromium_chromeos_rel_ng on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[jschuh, 2015-10-23 00:18:49]

The CQ bit was checked by jschuh@chromium.org

[commit-bot: I haz the power, 2015-10-23 00:19:27]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1415293006/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1415293006/1

[commit-bot: I haz the power, 2015-10-23 00:25:16]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-23 00:26:00]

Patchset 1 (id:??) landed as
https://crrev.com/8fc5ec7879e78806a00e6755e4bd8ab0ffd07df2
Cr-Commit-Position: refs/heads/master@{#355691}