GitLab

This CL makes OfflineItemModel inherit from DownloadUIModel

Bug: 881499
Change-Id: Ic7591f5ce7f5f5243cfeb8ff89ad1e77aa1b78db
Reviewed-on: https://chromium-review.googlesource.com/1237134
Commit-Queue: Min Qin <qinmin@chromium.org>
Reviewed-by: Shakti Sahu <shaktisahu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#593030}