PPAPI: Remove threading options; it's always on

PPAPI: Remove threading options; it's always on

This also re-enables thread checking for the host side resource and var trackers. Before, checking was disabled everywhere.

BUG=159240, 92909
Committed: r186925
Reverted: r186939 due to build errors

Committed: r187340

Committed: r187427
Reverted: r187668 due to a failing check in Canary, which was fixed here: r187681

Committed: r189518
Reverted: r189682, due to regression in Kraken (see crbug.com/222741)

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=191420
Reverted: r191441, due to new failing PDFResource unit test.

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=191510

[teravest, 2013-03-06 18:55:53]

lgtm

[raymes, 2013-03-07 18:09:33]

lgtm

Looks good, thanks.

I'm assuming you've grepped for ENABLE_PEPPER_THREADING and removed all the
references. 

As an aside, I hope that we can get rid of the host side resource tracker after
we finish the proxy refactoring effort (maybe also the host side var tracker).

[commit-bot: I haz the power, 2013-03-07 21:53:35]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmichael@chromium.org/12378050/21001

[commit-bot: I haz the power, 2013-03-07 21:53:49]

Presubmit check for 12378050-21001 failed and returned exit status 1.

INFO:root:Found 34 file(s).

Running presubmit commit checks ...
Running /b/commit-queue/workdir/chromium/PRESUBMIT.py
Running /b/commit-queue/workdir/chromium/chrome/PRESUBMIT.py
Running /b/commit-queue/workdir/chromium/ppapi/PRESUBMIT.py

** Presubmit ERRORS **
Missing LGTM from an OWNER for these files:
    content/ppapi_plugin/ppapi_thread.cc
    content/browser/ppapi_plugin_process_host.cc
    webkit/plugins/plugin_switches.h
    webkit/plugins/plugin_switches.cc

Presubmit checks took 4.5s to calculate.

[dmichael (off chromium), 2013-03-07 21:58:56]

+brettw for content and ppapi/plugins OWNERS review

[brettw, 2013-03-07 22:59:05]

LGTM rubberstamp

[commit-bot: I haz the power, 2013-03-07 23:11:49]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmichael@chromium.org/12378050/21001

[commit-bot: I haz the power, 2013-03-08 05:12:22]

Retried try job too often on win7_aura for step(s) content_browsertests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win7_aura&...

[commit-bot: I haz the power, 2013-03-08 07:18:39]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmichael@chromium.org/12378050/21001

[commit-bot: I haz the power, 2013-03-08 09:29:16]

Change committed as 186925

[commit-bot: I haz the power, 2013-03-08 19:17:42]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmichael@chromium.org/12378050/56001

[commit-bot: I haz the power, 2013-03-08 19:31:59]

Step "update" is always a major failure.
Look at the try server FAQ for more details.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=android_cl...

[commit-bot: I haz the power, 2013-03-11 17:06:03]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmichael@chromium.org/12378050/35004

[commit-bot: I haz the power, 2013-03-11 19:33:56]

Change committed as 187340

[commit-bot: I haz the power, 2013-03-11 21:30:18]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmichael@chromium.org/12378050/76003

[commit-bot: I haz the power, 2013-03-12 00:41:10]

Change committed as 187427

[commit-bot: I haz the power, 2013-03-20 16:25:24]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmichael@chromium.org/12378050/92010

[commit-bot: I haz the power, 2013-03-20 22:42:42]

Retried try job too often on win_rel for step(s) net_unittests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[commit-bot: I haz the power, 2013-03-20 23:00:34]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmichael@chromium.org/12378050/92010

[commit-bot: I haz the power, 2013-03-21 03:58:11]

Change committed as 189518

[commit-bot: I haz the power, 2013-03-28 22:38:32]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmichael@chromium.org/12378050/114001

[commit-bot: I haz the power, 2013-03-29 02:58:10]

Retried try job too often on win_rel for step(s) browser_tests,
chrome_frame_net_tests, chrome_frame_tests, chrome_frame_unittests,
content_browsertests, installer_util_unittests, mini_installer_test,
nacl_integration, sync_integration_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[commit-bot: I haz the power, 2013-03-29 15:20:02]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmichael@chromium.org/12378050/134001

[commit-bot: I haz the power, 2013-03-29 19:18:50]

Change committed as 191420

[commit-bot: I haz the power, 2013-03-29 21:26:57]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmichael@chromium.org/12378050/148001

[commit-bot: I haz the power, 2013-03-30 16:54:41]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmichael@chromium.org/12378050/148001

[commit-bot: I haz the power, 2013-03-30 17:08:15]

Change committed as 191510