CL:408662 was marked as code-review:+2 in patch:5, then commit-message was changed and malformed in patch:6. The label satisfied 'label:Code-Review=+2 AND -age:2h OR label:Trybot-Ready=+1' so Pre-commit-queue tried to pick it. when the Pre-Commit-Queue failed patch the CL, it only tried to reset the 'Commit-Queue' label and the 'Trybo-Ready' label. 

Going to reset 'Code-Review' to 0 (not -1/-2) in RemoveReady in Pre-CommitQueue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/chromite/+/4fcdebc37c7f479a0487524c4b3cc0655eba7292

commit 4fcdebc37c7f479a0487524c4b3cc0655eba7292
Author: Ningning Xia <nxia@chromium.org>
Date: Thu Feb 09 20:47:41 2017

Reset Code-Review label in Pre-CQ-Launcher

When a patch has BrokenCQDepends or BrokenChangeID exception,
Pre-CQ-Launcher may keep retrying it without marking it as not valid. If
Pre-CQ-Launcher catches these two exceptions, resets Code-Review,
Commit-Queue and Trybot-Ready labels and sends out the notification to
this CL.

BUG= chromium:663605 
TEST=unit_tests

Change-Id: Icd0391b18189d48a544c5790a26b21f2d067e3d8
Reviewed-on: https://chromium-review.googlesource.com/437600
Commit-Ready: Ningning Xia <nxia@chromium.org>
Tested-by: Ningning Xia <nxia@chromium.org>
Reviewed-by: Ningning Xia <nxia@chromium.org>

[modify] https://crrev.com/4fcdebc37c7f479a0487524c4b3cc0655eba7292/lib/gerrit_unittest.py
[modify] https://crrev.com/4fcdebc37c7f479a0487524c4b3cc0655eba7292/cbuildbot/validation_pool.py
[modify] https://crrev.com/4fcdebc37c7f479a0487524c4b3cc0655eba7292/lib/gerrit.py
[modify] https://crrev.com/4fcdebc37c7f479a0487524c4b3cc0655eba7292/cbuildbot/validation_pool_unittest.py

need to revert the fix.

 crbug.com/698928  chrome-bot cannot reset code-review labels for other users. need to find another way to fix this.

Revert CL at https://chromium-review.googlesource.com/c/453879/

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/chromite/+/ee04ec5de1bf776c9e481649ea093ac1622bf624

commit ee04ec5de1bf776c9e481649ea093ac1622bf624
Author: Ningning Xia <nxia@chromium.org>
Date: Tue Mar 14 02:58:54 2017

Revert "Reset Code-Review label in Pre-CQ-Launcher"

This reverts commit 4fcdebc37c7f479a0487524c4b3cc0655eba7292.

Reason for revert: <INSERT REASONING HERE>

Original change's description:
> Reset Code-Review label in Pre-CQ-Launcher
>
> When a patch has BrokenCQDepends or BrokenChangeID exception,
> Pre-CQ-Launcher may keep retrying it without marking it as not valid. If
> Pre-CQ-Launcher catches these two exceptions, resets Code-Review,
> Commit-Queue and Trybot-Ready labels and sends out the notification to
> this CL.
>
> BUG= chromium:663605 
> TEST=unit_tests
>
> Change-Id: Icd0391b18189d48a544c5790a26b21f2d067e3d8
> Reviewed-on: https://chromium-review.googlesource.com/437600
> Commit-Ready: Ningning Xia <nxia@chromium.org>
> Tested-by: Ningning Xia <nxia@chromium.org>
> Reviewed-by: Ningning Xia <nxia@chromium.org>
>

TBR=sbasi@chromium.org,3su6n15k.default@developer.gserviceaccount.com,nxia@chromium.org,chingcodes@chromium.org
BUG= chromium:663605 
TEST=unit_tests

Change-Id: I6fd03c3c4880b0413679898b7d242f308a9766b1
Reviewed-on: https://chromium-review.googlesource.com/453879
Commit-Ready: Ningning Xia <nxia@chromium.org>
Tested-by: Ningning Xia <nxia@chromium.org>
Reviewed-by: Xixuan Wu <xixuan@chromium.org>

[modify] https://crrev.com/ee04ec5de1bf776c9e481649ea093ac1622bf624/lib/gerrit_unittest.py
[modify] https://crrev.com/ee04ec5de1bf776c9e481649ea093ac1622bf624/cbuildbot/validation_pool.py
[modify] https://crrev.com/ee04ec5de1bf776c9e481649ea093ac1622bf624/lib/gerrit.py
[modify] https://crrev.com/ee04ec5de1bf776c9e481649ea093ac1622bf624/cbuildbot/validation_pool_unittest.py

Issue 733698 has been merged into this issue.

 Issue 748265  has been merged into this issue.