Revert of Re-land chromeos: Add non-extension renderers to the freezer cgroup

Revert of Re-land chromeos: Add non-extension renderers to the freezer cgroup (patchset #3 id:40001 of https://codereview.chromium.org/738993002/)

Reason for revert:
Crashes (especially on login)

BUG=364339, 437962
Original issue's description:
> Re-land chromeos: Add non-extension renderers to the freezer cgroup
>
> In preparation for lucid sleep, we will be putting all chrome renderers
> that do not host GCM extensions into a special freezer cgroup.  All
> processes in this cgroup will be frozen when the system suspends and
> will not be thawed until the system has fully resumed.
>
> The code to freeze and thaw the cgroup has existed for a while.  This
> code actually starts putting processes into the cgroup.
>
> Additionally, to deal with potential races that may occur with other
> suspend observers that interact with renderers, the RendererFreezer is
> no longer a PowerManagerClient::Observer but is instead a
> PowerManagerClient::RenderProcessManagerDelegate.  This guarantees that
> the RendererFreezer's suspend related methods will be called only after
> all observers have reported ready and before observers are notified that
> the suspend has completed.  Any race conditions that still exist now
> need to be fixed in the observer that is causing it.
>
> BUG=364339
>
> Committed: https://crrev.com/1a085efa9263279b58d6fd06ba991709d598f796
> Cr-Commit-Position: refs/heads/master@{#304956}

TBR=derat@chromium.org,chirantan@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=364339
Committed: https://crrev.com/387356b291bfb0e278bb350e0d1e492107a292e4
Cr-Commit-Position: refs/heads/master@{#306269}

[spang, 2014-12-01 22:19:09]

Created Revert of Re-land chromeos: Add non-extension renderers to the freezer
cgroup

[commit-bot: I haz the power, 2014-12-01 22:20:30]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/753313005/1

[commit-bot: I haz the power, 2014-12-01 22:21:25]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-12-01 22:22:11]

Patchset 1 (id:??) landed as
https://crrev.com/387356b291bfb0e278bb350e0d1e492107a292e4
Cr-Commit-Position: refs/heads/master@{#306269}