[Android] Fix provisioning for perf bots on L and/or user builds.

[Android] Fix provisioning for perf bots on L and/or user builds.

BUG=405950
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=291231

[jbudorick, 2014-08-21 17:09:34]

Fixing a couple of issues from the parallel provisioning CL:
 - Reboots on L are timing out on a couple of the perf bots.
 - old provisioning ignored adb root failures, now this does (with a warning),
too.

The timeout stuff is crude, but should work. provision_devices will now take
longer if devices don't come back after reboots, so I'll tune the timeout by OS
version in a future CL.

[tonyg, 2014-08-21 17:12:58]

https://codereview.chromium.org/495123002/diff/1/build/android/provision_devi...
File build/android/provision_devices.py (right):

https://codereview.chromium.org/495123002/diff/1/build/android/provision_devi...
build/android/provision_devices.py:154: device.EnableRoot()
I think the old code would skip the wipe if we couldn't enable root. Because the
wipe'll break adb on user builds. Does the new code do that too? If so, lgtm

[jbudorick, 2014-08-21 17:15:15]

https://codereview.chromium.org/495123002/diff/1/build/android/provision_devi...
File build/android/provision_devices.py (right):

https://codereview.chromium.org/495123002/diff/1/build/android/provision_devi...
build/android/provision_devices.py:141: device.EnableRoot()
@tonyg: it'll skip the wipe here. if we can't enable root, this will raise an
exception which will then be caught on line 145

[jbudorick, 2014-08-21 17:15:19]

The CQ bit was checked by jbudorick@chromium.org

[commit-bot: I haz the power, 2014-08-21 17:16:40]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jbudorick@chromium.org/495123002/1

[commit-bot: I haz the power, 2014-08-21 23:15:59]

Committed patchset #1 (1) as 291231