Revert of Revert of Re-enabling fixed WebRTC getusermedia tests.

Revert of Revert of Re-enabling fixed WebRTC getusermedia tests. (patchset #1 id:1 of https://codereview.chromium.org/630143002/)

Reason for revert:
Should be fixed by https://codereview.chromium.org/638423002/ and https://codereview.chromium.org/640253002.

Original issue's description:
> Revert of Re-enabling fixed WebRTC getusermedia tests. (patchset #1 id:1 of https://codereview.chromium.org/623733002/)
>
> Reason for revert:
> still flaky, see bug
>
> Original issue's description:
> > Re-enabling fixed WebRTC getusermedia tests.
> >
> > BUG=417756
> >
> > Committed: https://crrev.com/9fa6d13fdbac6c82917c23c9b63b4f3cb7b7593e
> > Cr-Commit-Position: refs/heads/master@{#298205}
>
> TBR=perkj@chromium.org,kjellander@chromium.org,phoglund@chromium.org
> NOTREECHECKS=true
> NOTRY=true
> BUG=417756
>
> Committed: https://crrev.com/290d2cfa5187ac1f2c87fde4c6dd6f27dad0c93a
> Cr-Commit-Position: refs/heads/master@{#298262}

TBR=perkj@chromium.org,kjellander@chromium.org,jam@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=417756
Committed: https://crrev.com/9a09162adb3d7c73cca55c40e5d1aa5c26d005fa
Cr-Commit-Position: refs/heads/master@{#299078}

[phoglund_chromium, 2014-10-10 08:49:41]

Created Revert of Revert of Re-enabling fixed WebRTC getusermedia tests.

[commit-bot: I haz the power, 2014-10-10 08:50:45]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/644873003/1

[commit-bot: I haz the power, 2014-10-10 08:51:19]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-10-10 08:52:13]

Patchset 1 (id:??) landed as
https://crrev.com/9a09162adb3d7c73cca55c40e5d1aa5c26d005fa
Cr-Commit-Position: refs/heads/master@{#299078}