[test] Fix deterministic test shards.

[test] Fix deterministic test shards.

Test case objects were sorted without key function, resulting
in random sort order. On sharded builds, the shards are
determined by the sort order and rely on a deterministic
sorting. This led to random cctest and unittest cases being
dropped or executed twice on sharded testers.

TBR=jkummerow@chromium.org, hablich@chromium.org

Committed: https://crrev.com/a0aac3cb1d30e8b3949df6827243a49e6d95c2ed
Cr-Commit-Position: refs/heads/master@{#35151}

[Michael Achenbach, 2016-03-29 08:11:06]

Description was changed from

==========
[test] Fix deterministic test shards.

BUG=
==========

to

==========
[test] Fix deterministic test shards.

Test case objects were sorted without key function, resulting
in random sort order. On sharded builds, the shards are
determined by the sort order and rely on a deterministic
sorting. This led to random cctest and unittest cases being
dropped or executed twice on sharded testers.
==========

[Michael Achenbach, 2016-03-29 08:11:06]

machenbach@chromium.org changed reviewers:
+ jkummerow@chromium.org

[Michael Achenbach, 2016-03-29 08:13:54]

PTAL. This bug was in there for quite some time. Impact got worse since we have
many bots with shards. Randomly missing coverage on the coverage bot made me
looking for it.

Repro: Repeatedly run and compare the output of:
tools/run-tests.py --arch x64 --mode Release --buildbot  unittests
--progress=verbose --shard-count=4 --shard-run=1 | grep "Done running" | sort |
awk '{ print $3 }'

Should be the same each time but is rather random.

[Michael Achenbach, 2016-03-29 12:53:30]

The CQ bit was checked by machenbach@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-03-29 12:53:38]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1842673002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1842673002/20001

[commit-bot: I haz the power, 2016-03-29 14:51:24]

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

[commit-bot: I haz the power, 2016-03-29 14:51:25]

Dry run: This issue passed the CQ dry run.

[Michael Achenbach, 2016-03-31 07:16:32]

Description was changed from

==========
[test] Fix deterministic test shards.

Test case objects were sorted without key function, resulting
in random sort order. On sharded builds, the shards are
determined by the sort order and rely on a deterministic
sorting. This led to random cctest and unittest cases being
dropped or executed twice on sharded testers.
==========

to

==========
[test] Fix deterministic test shards.

Test case objects were sorted without key function, resulting
in random sort order. On sharded builds, the shards are
determined by the sort order and rely on a deterministic
sorting. This led to random cctest and unittest cases being
dropped or executed twice on sharded testers.

TBR=jkummerow@chromium.org, hablich@chromium.org
==========

[Michael Achenbach, 2016-03-31 07:16:32]

machenbach@chromium.org changed reviewers:
+ hablich@chromium.org

[Michael Achenbach, 2016-03-31 07:16:50]

TBR as this fixes an annoying bug.

[Michael Achenbach, 2016-03-31 07:16:58]

The CQ bit was checked by machenbach@chromium.org

[commit-bot: I haz the power, 2016-03-31 07:17:02]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1842673002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1842673002/20001

[commit-bot: I haz the power, 2016-03-31 07:38:14]

Description was changed from

==========
[test] Fix deterministic test shards.

Test case objects were sorted without key function, resulting
in random sort order. On sharded builds, the shards are
determined by the sort order and rely on a deterministic
sorting. This led to random cctest and unittest cases being
dropped or executed twice on sharded testers.

TBR=jkummerow@chromium.org, hablich@chromium.org
==========

to

==========
[test] Fix deterministic test shards.

Test case objects were sorted without key function, resulting
in random sort order. On sharded builds, the shards are
determined by the sort order and rely on a deterministic
sorting. This led to random cctest and unittest cases being
dropped or executed twice on sharded testers.

TBR=jkummerow@chromium.org, hablich@chromium.org
==========

[commit-bot: I haz the power, 2016-03-31 07:38:14]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-03-31 07:38:27]

Description was changed from

==========
[test] Fix deterministic test shards.

Test case objects were sorted without key function, resulting
in random sort order. On sharded builds, the shards are
determined by the sort order and rely on a deterministic
sorting. This led to random cctest and unittest cases being
dropped or executed twice on sharded testers.

TBR=jkummerow@chromium.org, hablich@chromium.org
==========

to

==========
[test] Fix deterministic test shards.

Test case objects were sorted without key function, resulting
in random sort order. On sharded builds, the shards are
determined by the sort order and rely on a deterministic
sorting. This led to random cctest and unittest cases being
dropped or executed twice on sharded testers.

TBR=jkummerow@chromium.org, hablich@chromium.org

Committed: https://crrev.com/a0aac3cb1d30e8b3949df6827243a49e6d95c2ed
Cr-Commit-Position: refs/heads/master@{#35151}
==========

[commit-bot: I haz the power, 2016-03-31 07:38:28]

Patchset 2 (id:??) landed as
https://crrev.com/a0aac3cb1d30e8b3949df6827243a49e6d95c2ed
Cr-Commit-Position: refs/heads/master@{#35151}

[Jakob Kummerow, 2016-04-05 08:12:00]

lgtm