Gitiles: commit's author and committer are the same structures.
Gitiles: commit's author and committer are the same structures.

BUG=646067

Review-Url: https://codereview.chromium.org/2981753002

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