cc: Fix invalid opaque debug quads

cc: Fix invalid opaque debug quads

It's possible that small debug border quads (when opaque) can get inset
so much that they become empty.  This causes problems in IPC validating,
as the quad rect no longer contains the visible rect (which is empty,
due to the insetting).  This causes the frame to be invalid, which
causes browser rendering artifacts.

BUG=472014
Committed: https://crrev.com/b79d5f14c97e62d10fa9b556eef4f50297049036
Cr-Commit-Position: refs/heads/master@{#326618}

[enne (OOO), 2015-04-23 01:42:44]

enne@chromium.org changed reviewers:
+ danakj@chromium.org

[danakj, 2015-04-23 16:42:53]

LGTM

[enne (OOO), 2015-04-23 18:41:15]

The CQ bit was checked by enne@chromium.org

[commit-bot: I haz the power, 2015-04-23 18:42:14]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1105573002/1

[commit-bot: I haz the power, 2015-04-23 20:00:02]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-04-23 20:01:14]

Patchset 1 (id:??) landed as
https://crrev.com/b79d5f14c97e62d10fa9b556eef4f50297049036
Cr-Commit-Position: refs/heads/master@{#326618}