[Telemetry] fix maps.py benchmark

[Telemetry] fix maps.py benchmark

The value of total time and render time from regular expression matching
are strings, not numbers. Do the conversion before adding to scalar
value.

BUG=None

Committed: https://crrev.com/c91bd8a528f440c899afb84cf5a17545aecc9778
Cr-Commit-Position: refs/heads/master@{#315958}

[deanliao, 2015-02-11 09:11:45]

deanliao@chromium.org changed reviewers:
+ aiolos@chromium.org, bajones@chromium.org

[bajones, 2015-02-11 17:10:48]

lgtm

[deanliao, 2015-02-12 03:49:43]

deanliao@chromium.org changed reviewers:
+ nednguyen@google.com

[nednguyen, 2015-02-12 03:58:00]

lgtm

[deanliao, 2015-02-12 04:47:05]

deanliao@chromium.org changed reviewers:
- aiolos@chromium.org

[deanliao, 2015-02-12 09:34:25]

The CQ bit was checked by deanliao@chromium.org

[commit-bot: I haz the power, 2015-02-12 09:35:17]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/876063004/1

[commit-bot: I haz the power, 2015-02-12 11:20:29]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-12 11:21:09]

Patchset 1 (id:??) landed as
https://crrev.com/c91bd8a528f440c899afb84cf5a17545aecc9778
Cr-Commit-Position: refs/heads/master@{#315958}