Make debug on start checkbox on service worker internals page easier to click.

Make debug on start checkbox on service worker internals page easier to click.

This patch wraps the debug on start checkbox on service worker internals page into a label element
to allow clicking on the text near the checkbox as well as the checkbox itself.
R=horo

Committed: https://crrev.com/e6492dbcddf1845779da22d0de309bb9e496dd2c
Cr-Commit-Position: refs/heads/master@{#294302}

[vsevik, 2014-09-10 23:21:32]

PTAL

[horo, 2014-09-11 00:52:59]

lgtm

[vsevik, 2014-09-11 01:03:06]

The CQ bit was checked by vsevik@chromium.org

[commit-bot: I haz the power, 2014-09-11 01:05:52]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patchset/558353002/1

[commit-bot: I haz the power, 2014-09-11 02:49:17]

Committed patchset #1 (id:1) as 8b3911d3bf5f8a5f2fd4e2c5d1123cd270d90c0c

[commit-bot: I haz the power, 2014-09-11 03:09:26]

Patchset 1 (id:??) landed as
https://crrev.com/e6492dbcddf1845779da22d0de309bb9e496dd2c
Cr-Commit-Position: refs/heads/master@{#294302}