Revert of Add support for codepen to form_based_credentials_background

Revert of Add support for codepen to form_based_credentials_background (patchset #9 of https://codereview.chromium.org/485743002/)

Reason for revert:
The test change is causing flakiness on trybots even with retries, see

telemetry/core/backends/google_credentials_backend_unittest/TestGoogleCredentialsBackend/testLoginUsingMock:

http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_rel_swarming/builds/5713
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_rel_swarming/builds/5703
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_swarming/builds/6959
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_rel_swarming/builds/9980
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_rel_swarming/builds/9973
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_x64_rel_swarming/builds/2974
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_x64_rel_swarming/builds/2966
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_swarming/builds/6950

Original issue's description:
> Add support for codepen to form_based_credentials_background
> 
> Fix google credentials support.
> 
> Migrate to action_runner when possible.
> 
> BUG=
> 
> Committed: https://chromium.googlesource.com/chromium/src/+/a64e885edb85f66035f35a848c0add3726a663af

TBR=tonyg@chromium.org,sullivan@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=

Committed: https://crrev.com/aee4c9f50df8c0ab073c4313b292c3f5276d0b00
Cr-Commit-Position: refs/heads/master@{#291925}

[jam, 2014-08-26 17:20:46]

Created Revert of Add support for codepen to form_based_credentials_background

[commit-bot: I haz the power, 2014-08-26 17:21:56]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jam@chromium.org/502533003/1

[commit-bot: I haz the power, 2014-08-26 17:22:59]

Committed patchset #1 (1) as c52c77ac119b370321edaeb3f8346887ecea31c8

[commit-bot: I haz the power, 2014-09-10 02:43:33]

Patchset 1 (id:??) landed as
https://crrev.com/aee4c9f50df8c0ab073c4313b292c3f5276d0b00
Cr-Commit-Position: refs/heads/master@{#291925}