Revert 233048 "Support policies referencing external data for de..."
The CL broke compilation on Chrome OS.
> Support policies referencing external data for device-local accounts
>
> This CL adds a DeviceLocalAccountExternalDataService that provides each
> device-local account with a DeviceLocalAccountExternalDataManager which
> fetches, caches and retrieves external policy data.
>
> BUG=256635
> TEST=New browser test
> R=derat@chromium.org, joaodasilva@chromium.org
>
> Review URL: https://codereview.chromium.org/
25242002
TBR=bartfab@chromium.org
Review URL: https://codereview.chromium.org/
60683002
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233051 0039d316-1c4b-4281-b951-d872f2087c98