GitLab

This cleans up ui/display to use base::OnceCallback instead of
base::Callback where appropriate.

Bug: 714018
Test: CQ & run chrome on eve

Change-Id: I4231d9266f2d7df41701fe70fa8ef4a9b42b34c4
Reviewed-on: https://chromium-review.googlesource.com/1026553Reviewed-by: Daniel Nicoara <dnicoara@chromium.org>
Reviewed-by: kylechar <kylechar@chromium.org>
Commit-Queue: Michael Spang <spang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#553643}