Detect duplicate USB device notifications from udev.

Detect duplicate USB device notifications from udev.

This patch adds a check to detect when udev has sent Chrome multiple
notifications for the same device, ignoring the duplicates, as this
behavior has been observed in the wild.

I also fix DeviceReady() to not send a device added notification if a
device was disconnected while it was being enumerated. The device would
not have been added to the global device list in this case.

BUG=638298
Committed: https://crrev.com/f2c7b56f4a4f2c16b2f7062f60ad3041217e9f20
Cr-Commit-Position: refs/heads/master@{#413273}

[Reilly Grant (use Gerrit), 2016-08-19 21:17:45]

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

[Reilly Grant (use Gerrit), 2016-08-19 21:17:46]

Please take a look.

[juncai, 2016-08-19 21:51:41]

LGTM.

[Reilly Grant (use Gerrit), 2016-08-19 21:56:02]

The CQ bit was checked by reillyg@chromium.org

[commit-bot: I haz the power, 2016-08-19 21:56:46]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-19 22:52:20]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-08-19 22:54:09]

Description was changed from

==========
Detect duplicate USB device notifications from udev.

This patch adds a check to detect when udev has sent Chrome multiple
notifications for the same device, ignoring the duplicates, as this
behavior has been observed in the wild.

I also fix DeviceReady() to not send a device added notification if a
device was disconnected while it was being enumerated. The device would
not have been added to the global device list in this case.

BUG=638298
==========

to

==========
Detect duplicate USB device notifications from udev.

This patch adds a check to detect when udev has sent Chrome multiple
notifications for the same device, ignoring the duplicates, as this
behavior has been observed in the wild.

I also fix DeviceReady() to not send a device added notification if a
device was disconnected while it was being enumerated. The device would
not have been added to the global device list in this case.

BUG=638298

Committed: https://crrev.com/f2c7b56f4a4f2c16b2f7062f60ad3041217e9f20
Cr-Commit-Position: refs/heads/master@{#413273}
==========

[commit-bot: I haz the power, 2016-08-19 22:54:10]

Patchset 1 (id:??) landed as
https://crrev.com/f2c7b56f4a4f2c16b2f7062f60ad3041217e9f20
Cr-Commit-Position: refs/heads/master@{#413273}