Ensure libusb_close is called from the FILE thread.

Ensure libusb_close is called from the FILE thread.

If libusb_close is called from the UsbEventHandler thread then it will
deadlock trying to reacquire libusb's open_devs_lock. To avoid this and
generally ensure that libusb calls happen on the FILE thread this patch
posts a task if the UsbDeviceHandleImpl destructor is not already
running on the FILE thread.

BUG=589592
Committed: https://crrev.com/449dde0f87ac33b516a1186398d17edbd75e4ee9
Cr-Commit-Position: refs/heads/master@{#377821}

[Reilly Grant (use Gerrit), 2016-02-24 23:54:16]

reillyg@chromium.org changed reviewers:
+ rockot@chromium.org

[Reilly Grant (use Gerrit), 2016-02-24 23:54:17]

Please take a look.

[Reilly Grant (use Gerrit), 2016-02-26 02:03:55]

Ping.

[Ken Rockot(use gerrit already), 2016-02-26 02:04:38]

lgtm

[Reilly Grant (use Gerrit), 2016-02-26 02:07:34]

The CQ bit was checked by reillyg@chromium.org

[commit-bot: I haz the power, 2016-02-26 02:08:17]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1736703002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1736703002/1

[commit-bot: I haz the power, 2016-02-26 02:38:01]

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

[commit-bot: I haz the power, 2016-02-26 02:38:02]

Try jobs failed on following builders:
  android_chromium_gn_compile_rel on tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/android_chro...)
  linux_chromium_asan_rel_ng on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[Reilly Grant (use Gerrit), 2016-02-26 02:39:30]

The CQ bit was checked by reillyg@chromium.org

[commit-bot: I haz the power, 2016-02-26 02:43:09]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1736703002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1736703002/1

[commit-bot: I haz the power, 2016-02-26 03:20:50]

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

[commit-bot: I haz the power, 2016-02-26 03:20:51]

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

[Reilly Grant (use Gerrit), 2016-02-26 04:57:06]

The CQ bit was checked by reillyg@chromium.org

[commit-bot: I haz the power, 2016-02-26 04:58:17]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1736703002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1736703002/1

[commit-bot: I haz the power, 2016-02-26 05:42:56]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-02-26 05:43:59]

Description was changed from

==========
Ensure libusb_close is called from the FILE thread.

If libusb_close is called from the UsbEventHandler thread then it will
deadlock trying to reacquire libusb's open_devs_lock. To avoid this and
generally ensure that libusb calls happen on the FILE thread this patch
posts a task if the UsbDeviceHandleImpl destructor is not already
running on the FILE thread.

BUG=589592
==========

to

==========
Ensure libusb_close is called from the FILE thread.

If libusb_close is called from the UsbEventHandler thread then it will
deadlock trying to reacquire libusb's open_devs_lock. To avoid this and
generally ensure that libusb calls happen on the FILE thread this patch
posts a task if the UsbDeviceHandleImpl destructor is not already
running on the FILE thread.

BUG=589592

Committed: https://crrev.com/449dde0f87ac33b516a1186398d17edbd75e4ee9
Cr-Commit-Position: refs/heads/master@{#377821}
==========

[commit-bot: I haz the power, 2016-02-26 05:44:00]

Patchset 1 (id:??) landed as
https://crrev.com/449dde0f87ac33b516a1186398d17edbd75e4ee9
Cr-Commit-Position: refs/heads/master@{#377821}