Revert of Change WebRTC SslCipher to be exposed as number only.

Revert of Change WebRTC SslCipher to be exposed as number only. (patchset #20 id:750001 of https://codereview.webrtc.org/1337673002/ )

Reason for revert:
This broke chromium.fyi bot.

Original issue's description:
> Change WebRTC SslCipher to be exposed as number only.
> 
> This makes the SSL exposed as uint16_t which is the IANA value. GetRfcSslCipherName is introduced to handle the conversion to names from ID. IANA value will be used for UMA reporting. Names will still be used for WebRTC stats reporting.
> 
> For SRTP, currently it's still string internally but is reported as IANA number.
> 
> This is used by the ongoing CL https://codereview.chromium.org/1335023002.
> 
> BUG=523033
> 
> Committed: https://crrev.com/4fe3c9a77386598db9abd1f0d6983aefee9cc943
> Cr-Commit-Position: refs/heads/master@{#10124}

TBR=juberti@webrtc.org,rsleevi@chromium.org,pthatcher@webrtc.org,davidben@chromium.org,juberti@google.com,davidben@webrtc.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=523033

[guoweis_webrtc, 2015-10-01 02:22:49]

Created Revert of Change WebRTC SslCipher to be exposed as number only.

[commit-bot: I haz the power, 2015-10-01 02:23:01]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1380603005/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1380603005/1

[commit-bot: I haz the power, 2015-10-01 02:23:20]

Patchset 1 (id:??) landed as
https://crrev.com/27dc29b0df23eed5034f28d4d5f66ea0bb425d6c
Cr-Commit-Position: refs/heads/master@{#10125}

[commit-bot: I haz the power, 2015-10-01 02:23:23]

Committed patchset #1 (id:1)