Roll tools/swarming_client/ to d863df38343f8057dbddfe5543addcf19a49ce0f.

Roll tools/swarming_client/ to d863df38343f8057dbddfe5543addcf19a49ce0f.

$ git log e98dde9a7..d863df383 --date=short --format='%ad %ae %s' | sed 's/@chromium\.org//'
2015-01-24 maruel Set the parent task id when SWARMING_TASK_ID is set.
2015-01-23 maruel Print a proper error message instead of printing a stack trace on failure.

R=vadimsh@chromium.org
BUG=

Committed: https://crrev.com/68785f08af13e3f6dcc5599f9d5b1a9b630bfd46
Cr-Commit-Position: refs/heads/master@{#313039}

[Vadim Sh., 2015-01-25 21:40:08]

lgtm

[M-A Ruel, 2015-01-25 21:48:51]

The CQ bit was checked by maruel@chromium.org

[commit-bot: I haz the power, 2015-01-25 21:49:42]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/871263002/1

[commit-bot: I haz the power, 2015-01-25 21:53:00]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-01-25 21:53:51]

Patchset 1 (id:??) landed as
https://crrev.com/68785f08af13e3f6dcc5599f9d5b1a9b630bfd46
Cr-Commit-Position: refs/heads/master@{#313039}