Abort SandboxedUnpacker::RewriteImageFiles on browser shutdown

Abort SandboxedUnpacker::RewriteImageFiles on browser shutdown

Add ability to check if shutdown was initiated for threading pool.

BUG=235525
TEST=run existing tests

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=210917

[Dmitry Polukhin, 2013-07-04 14:50:47]

brettw@ for OWNER review in base/

[asargent_no_longer_on_chrome, 2013-07-08 21:19:58]

LGTM

[Dmitry Polukhin, 2013-07-09 09:34:40]

Brett, please take a look to base/* changes, I need OWNER review there.

[Dmitry Polukhin, 2013-07-10 13:38:26]

+ jar@ for OWNER review in base/threading/sequenced_worker_pool.*

[jar (doing other things), 2013-07-10 15:07:05]

base changes LGTM %nit

https://codereview.chromium.org/18690003/diff/1/base/threading/sequenced_work...
File base/threading/sequenced_worker_pool.h (right):

https://codereview.chromium.org/18690003/diff/1/base/threading/sequenced_work...
base/threading/sequenced_worker_pool.h:320: // for aborting time consuming
operation to don't block shutdown.
nit: typo:

"...to don't block shutdown." --> "...to avoid blocking shutdown."

[Dmitry Polukhin, 2013-07-10 17:24:22]

https://codereview.chromium.org/18690003/diff/1/base/threading/sequenced_work...
File base/threading/sequenced_worker_pool.h (right):

https://codereview.chromium.org/18690003/diff/1/base/threading/sequenced_work...
base/threading/sequenced_worker_pool.h:320: // for aborting time consuming
operation to don't block shutdown.
On 2013/07/10 15:07:06, jar wrote:
> nit: typo:
> 
> "...to don't block shutdown." --> "...to avoid blocking shutdown."

Done.

[commit-bot: I haz the power, 2013-07-10 17:25:23]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dpolukhin@chromium.org/18690003/24001

[commit-bot: I haz the power, 2013-07-10 20:19:26]

Change committed as 210917