Revert "Hold the Pepper proxy lock for all Pepper GL calls."

Revert "Hold the Pepper proxy lock for all Pepper GL calls."

This reverts commit 5a9a39b79e40a322b7f6c2d8051f99a49f2fe598.

The commit is causing ARC apps to deadlock.

BUG=435414
Committed: https://crrev.com/4cdb1559546c2e96ceb566c2b6dc60cf08384663
Cr-Commit-Position: refs/heads/master@{#307059}

[benhansen, 2014-12-04 21:57:44]

benhansen@chromium.org changed reviewers:
+ piman@chromium.org

[dmichael (off chromium), 2014-12-05 18:40:21]

dmichael@chromium.org changed reviewers:
+ dmichael@chromium.org

[dmichael (off chromium), 2014-12-05 18:40:21]

lgtm

The real problem is that we sometimes attempt to acquire the ProxyLock on the IO
thread. But in the mean time before that's fixed, we should revert this to
unblock you (and an external partner who noticed the same issue)

[dmichael (off chromium), 2014-12-05 18:40:31]

The CQ bit was checked by dmichael@chromium.org

[commit-bot: I haz the power, 2014-12-05 18:40:58]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/774763005/1

[commit-bot: I haz the power, 2014-12-05 19:32:50]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-12-05 19:33:43]

Patchset 1 (id:??) landed as
https://crrev.com/4cdb1559546c2e96ceb566c2b6dc60cf08384663
Cr-Commit-Position: refs/heads/master@{#307059}