Reason for revert:
Fix
Original issue's description:
> Revert of Log created probe clusters to RtcEventLog. (patchset #1 id:1 of https://codereview.chromium.org/2783693002/ )
>
> Reason for revert:
> Break bots.
>
> Original issue's description:
...
>
> TBR=terelius@webrtc.org,stefan@webrtc.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=webrtc:6984
>
> Review-Url: https://codereview.webrtc.org/2781853002
> Cr-Commit-Position: refs/heads/master@{#17425}
> Committed: e3b354bdfa
TBR=terelius@webrtc.org,stefan@webrtc.org
BUG=webrtc:6984
Review-Url: https://codereview.webrtc.org/2779893004
Cr-Commit-Position: refs/heads/master@{#17433}