GitLab

DownloadFilter is used by non-UI code and should be moved out.
BackendProvider is not needed and can be removed.

BUG=1013759

Change-Id: I88d346e9035171fff4d371c77df3812e93a857b6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1865537Reviewed-by: Shakti Sahu <shaktisahu@chromium.org>
Reviewed-by: David Trainor <dtrainor@chromium.org>
Commit-Queue: Min Qin <qinmin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#706919}