cv: log the events received by RunManager
cv: log the events received by RunManager

R=tandrii

Change-Id: If210fb9012135383415ec7bec1a7ec25e090ee84
Reviewed-on: https://chromium-review.googlesource.com/c/infra/luci/luci-go/+/3183661
Auto-Submit: Yiwei Zhang <50b2a565e2e78c292794832469a30ce5abc9959c@google.com>
Commit-Queue: Andrii Shyshkalov <a30c74fa30536fe7ea81ed6dec202e35e149e1fd@google.com>
Reviewed-by: Andrii Shyshkalov <a30c74fa30536fe7ea81ed6dec202e35e149e1fd@google.com>

luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go