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 Review URL: https://codereview.webrtc.org/1337673002 Cr-Commit-Position: refs/heads/master@{#10124}