Fix unbounded allocation of GL queries

Fix unbounded allocation of GL queries

Check to see if previously-allocated queries are done before allocating
new ones. It turns out that destroying a massive list of queries
accounts for 50% of our watchdog timeouts in the GPU process.

BUG=398072
Committed: https://crrev.com/b4cce56ab9c457efe70cb142929308e04bbd8522
Cr-Commit-Position: refs/heads/master@{#299164}

[ccameron, 2014-10-10 00:13:27]

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

[ccameron, 2014-10-10 00:13:28]

So, this was funny.

[enne (OOO), 2014-10-10 18:23:03]

Oh, my.  lgtm

+reveman FYI

[ccameron, 2014-10-10 18:32:02]

Thanks!

[ccameron, 2014-10-10 18:32:05]

The CQ bit was checked by ccameron@chromium.org

[commit-bot: I haz the power, 2014-10-10 18:32:58]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/642993002/1

[commit-bot: I haz the power, 2014-10-10 19:45:39]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-10-10 19:46:23]

Patchset 1 (id:??) landed as
https://crrev.com/b4cce56ab9c457efe70cb142929308e04bbd8522
Cr-Commit-Position: refs/heads/master@{#299164}