Reland "Don't send download pings if the download is cancelled"

This reverts commit bb4a37675c5397ed15e27b9e2cafbc4b45e21b96. The
previous version had the problem that RunUntilIdle() was running
inconsistent amounts of tasks, which led to failed EXPECT_CALLs. I've
removed the RunUntilIdle() by ensuring the CheckClientDownload always
runs its callback, even when the download is destroyed. This is a minor
behavior change, but doesn't seem to break anything (the download code
doesn't assume the download item exists, so it handles the download
destroyed case correctly).

Change-Id: Ic036eefa5e1ad97be7bef72b172296112b077e11
Bug: 930372
Reviewed-on: https://chromium-review.googlesource.com/c/1460177
Commit-Queue: Daniel Rubery <drubery@chromium.org>
Reviewed-by: Varun Khaneja <vakh@chromium.org>
Reviewed-by: Nathan Parker <nparker@chromium.org>
Cr-Commit-Position: refs/heads/master@{#631000}
2 files changed