Revert of Use BoringSSL in the implementation of ClearKey for Chromecast.

Revert of Use BoringSSL in the implementation of ClearKey for Chromecast. (patchset #1 id:1 of https://codereview.chromium.org/1130893008/)

Reason for revert:
Temporary revert until Monday (blocked on some other internal changes).

Original issue's description:
> Use BoringSSL in the implementation of ClearKey for Chromecast.
> (Previously, this was used only with the "Chrome" branding).
>
> BUG=488572
>
> R=gunsch@chromium.org
>
> Committed: https://crrev.com/defd2af08f3753687cb2d86b34bbec9da31ccbab
> Cr-Commit-Position: refs/heads/master@{#330156}

TBR=ddorwin@chromium.org,dougsteed@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=488572
Committed: https://crrev.com/564d81833f28f73b9413c6d01725530ff91de64c
Cr-Commit-Position: refs/heads/master@{#330230}

[gunsch, 2015-05-15 23:22:38]

Created Revert of Use BoringSSL in the implementation of ClearKey for
Chromecast.

[commit-bot: I haz the power, 2015-05-15 23:24:27]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1141243003/1

[commit-bot: I haz the power, 2015-05-15 23:27:09]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-05-18 11:29:03]

Patchset 1 (id:??) landed as
https://crrev.com/564d81833f28f73b9413c6d01725530ff91de64c
Cr-Commit-Position: refs/heads/master@{#330230}

[gunsch, 2015-05-18 16:26:40]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/1148433002/ by gunsch@chromium.org.

The reason for reverting is: OK to replay now.