Revert of Add source column to chrome://policy showing the origins of policies.

Revert of Add source column to chrome://policy showing the origins of policies. (patchset #15 id:540001 of https://codereview.chromium.org/1304843004/ )

Reason for revert:
breaks compilation on iOS Device (ninja)

Original issue's description:
> Add source column to chrome://policy showing the origins of policies.
>
> These are the possible sources for a policy:
> Cloud - Policy values received from the cloud.
> Platform - Local configured policies.
> Enterprise Default - Defaults for policies in enterprise environments
>                      on Chrome OS. Can be overridden.
> Enterprise Override - Policies enforced in enterprise environments on
>                       Chrome OS. Can NOT be overridden.
>
> The source of a policy is determined when it's first set. For cloud
> policies, this would be the decoding of the protocol buffers.
> Platform policies are usually set by loading platform-specific local
> configurations like entries in the Windows registry.
> Enterprise defaults are automatically set if the device is active in
> an enterprise environment.
> Enterprise override policies are set within the code to enforce
> specific behaviors (like ash tray visibility). They cannot be
> overridden.
>
> BUG=506123
> TBR=jam@chromium.org
>
> Committed: https://crrev.com/92e7960f06c2ac2ec0113bb88df3d322f0eb97fe
> Cr-Commit-Position: refs/heads/master@{#349654}

TBR=tnagel@chromium.org,bartfab@chromium.org,dbeam@chromium.org,fhorschig@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=506123
Committed: https://crrev.com/cd10a8822ea05d981b67c7e9693b0132e3838cec
Cr-Commit-Position: refs/heads/master@{#349655}

[jochen (gone - plz use gerrit), 2015-09-18 12:49:34]

Created Revert of Add source column to chrome://policy showing the origins of
policies.

[commit-bot: I haz the power, 2015-09-18 12:49:41]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1348903007/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1348903007/1

[commit-bot: I haz the power, 2015-09-18 12:50:45]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-18 12:51:21]

Patchset 1 (id:??) landed as
https://crrev.com/cd10a8822ea05d981b67c7e9693b0132e3838cec
Cr-Commit-Position: refs/heads/master@{#349655}