Clean up out/<target> directory in the end if extract_build.

Clean up out/<target> directory in the end if extract_build.

Many slaves are shared between rel/dbg builders with the same build directory names. This makes sure we are testing what we intend to test.
BUG=401781
R=navabi@chromium.org, luqui@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=289042

[zty, 2014-08-08 22:10:22]

ptal

[luqui, 2014-08-11 19:22:18]

lgtm

[zty, 2014-08-11 19:39:52]

The CQ bit was checked by zty@chromium.org

[commit-bot: I haz the power, 2014-08-11 19:41:45]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/zty@chromium.org/452263002/1

[commit-bot: I haz the power, 2014-08-11 19:41:47]

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

[commit-bot: I haz the power, 2014-08-11 19:41:48]

No LGTM from a valid reviewer yet. Only full committers are accepted.
Even if an LGTM may have been provided, it was from a non-committer or
a provisional committer, _not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.

[navabi, 2014-08-11 21:37:53]

rs lgtm

[zty, 2014-08-11 21:38:14]

The CQ bit was checked by zty@chromium.org

[commit-bot: I haz the power, 2014-08-11 21:40:42]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/zty@chromium.org/452263002/1

[commit-bot: I haz the power, 2014-08-11 22:32:26]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  chromium_presubmit on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)

[commit-bot: I haz the power, 2014-08-11 22:38:26]

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

[commit-bot: I haz the power, 2014-08-11 22:38:30]

Try jobs failed on following builders:
  chromium_presubmit on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)

[navabi1, 2014-08-12 01:09:34]

lgtm

[zty, 2014-08-12 18:48:25]

The CQ bit was checked by zty@chromium.org

[commit-bot: I haz the power, 2014-08-12 18:51:19]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/zty@chromium.org/452263002/1

[commit-bot: I haz the power, 2014-08-12 19:05:31]

Change committed as 289042