GitLab

This CL calls the InProgressDownloadManager to delete ResourceDownloader
after response is completed.
It also fixes the issue when download is cancelled.

BUG=864189

Change-Id: I184d5faaace90f49874e45b4126a0a9821fdced7
Reviewed-on: https://chromium-review.googlesource.com/1138676
Commit-Queue: Min Qin <qinmin@chromium.org>
Reviewed-by: Xing Liu <xingliu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#575882}