Revert of PPAPI: Make tests that disable the proxy lock re-enable it

Revert of PPAPI: Make tests that disable the proxy lock re-enable it (patchset #2 id:20001 of https://codereview.chromium.org/908363002/)

Reason for revert:
Broke tests on Linux:
https://build.chromium.org/p/chromium.linux/builders/Linux%20Tests%20%28dbg%29%281%29%2832%29/builds/9607

Original issue's description:
> PPAPI: Make tests that disable the proxy lock re-enable it
>
> Rather than force all unit tests that rely on the ProxyLock to enable it,
> let's make sure that all tests that _disable_ it re-enable it on exit.
>
> BUG=
> R=teravest@chromium.org
>
> Committed: https://crrev.com/25ea5b2087b4c31fa42dea9b0de759d4895d0612
> Cr-Commit-Position: refs/heads/master@{#315666}

TBR=teravest@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=

Committed: https://crrev.com/a70de92b7f90d5e7b9e58a3ac87d800687d2c58e
Cr-Commit-Position: refs/heads/master@{#315686}

[dmichael (off chromium), 2015-02-11 00:22:36]

Created Revert of PPAPI: Make tests that disable the proxy lock re-enable it

[commit-bot: I haz the power, 2015-02-11 00:24:01]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/918433002/1

[commit-bot: I haz the power, 2015-02-11 00:24:52]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-11 00:25:24]

Patchset 1 (id:??) landed as
https://crrev.com/a70de92b7f90d5e7b9e58a3ac87d800687d2c58e
Cr-Commit-Position: refs/heads/master@{#315686}