This patch adds
- Attribute: STUN_ATTR_GOOG_MESSAGE_INTEGRITY_32
which is a ordinary message integrity but truncated to 32-bit
- Method: GOOG_PING,
which will be used for webrtc:11100
Both the attribute and the method has been registered at iana,
https://www.iana.org/assignments/stun-parameters/stun-parameters.xhtml#stun-parameters-4
BUG=webrtc:11100
Change-Id: Iddd5614473fd6f18fbbe76e72d047c617df7123f
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/160180
Commit-Queue: Jonas Oreland <jonaso@webrtc.org>
Reviewed-by: Björn Terelius <terelius@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29864}