[tools] Revert callstats.py group regexp changes

[tools] Revert callstats.py group regexp changes

The previous change accidentally shifted categories around which broke our
performance graphs.

BUG=

Committed: https://crrev.com/248b7a08b4394550c6169c47f2e168c2d0291c44
Cr-Commit-Position: refs/heads/master@{#39721}

[Camillo Bruni, 2016-09-26 09:06:04]

cbruni@chromium.org changed reviewers:
+ nikolaos@chromium.org

[Camillo Bruni, 2016-09-26 09:06:05]

PTAL

[nickie, 2016-09-26 09:19:55]

LGTM.

(Now, the previous CL also LGTM, so go figure...)

[Camillo Bruni, 2016-09-26 12:16:02]

The CQ bit was checked by cbruni@chromium.org

[commit-bot: I haz the power, 2016-09-26 12:16:06]

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, 2016-09-26 13:06:39]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-09-26 13:06:57]

Description was changed from

==========
[tools] Revert callstats.py group regexp changes

The previous change accidentally shifted categories around which broke our
performance graphs.

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

to

==========
[tools] Revert callstats.py group regexp changes

The previous change accidentally shifted categories around which broke our
performance graphs.

BUG=

Committed: https://crrev.com/248b7a08b4394550c6169c47f2e168c2d0291c44
Cr-Commit-Position: refs/heads/master@{#39721}
==========

[commit-bot: I haz the power, 2016-09-26 13:06:58]

Patchset 1 (id:??) landed as
https://crrev.com/248b7a08b4394550c6169c47f2e168c2d0291c44
Cr-Commit-Position: refs/heads/master@{#39721}