Migrate //chrome/browser/extensions/activity_log to OnceCallback

This updates //chrome/browser/extensions/activity_log to use
base::OnceCallback instead of legacy base::Callback. No intended
functional change is included.

This reduces the number of 'base::Bind' in
//chrome/browser/extensions/activity_log from 69 to 0 as tracked at
http://goo.gl/LUVhDj

Bug: 714018
Change-Id: I4fe44c7fada907f3a1c70971067c29f0d5492e8f
Reviewed-on: https://chromium-review.googlesource.com/952953
Commit-Queue: Taiju Tsuiki <tzik@chromium.org>
Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#541703}
11 files changed