Try to recover pending download missions when possible

[whistlingwoods]

What is it?

• Bugfix (user facing)
• Feature (user facing)
• Codebase improvement (dev facing)
• Meta improvement to the project (dev facing)

Description of the changes in your PR

This PR changes the app behavior where it considers ERROR_PROGRESS_LOST as invalid storage, however where it is possible to recover the pending download missions, it tries for that.

Fixes the following issue(s)

Fix app can't resume paused downloads in certain following situations:

• Fixes Pausing download/ejecting app while in progress makes download unrecoverable  #11076
• Fixes Unfinished Downloads Disappearing From Downloads List #7059 (a duplicate but most visited issue since it broke.)
• May Fix List of downloads refresh after turning on settings to "interrupt on metered networks" #9557
• May Fix Download queue deletes when switching to battery save mode #10527

APK testing

The APK can be found by going to the "Checks" tab below the title. On the left pane, click on "CI", scroll down to "artifacts" and click "app" to download the zip file which contains the debug APK of this PR. You can find more info and a video demonstration on this wiki page.

Due diligence

• I read the contribution guidelines.

[ShareASmile]

Steps to follow for rigorously testing the fix under different conditions:

1. Try to download a large file under unstable network conditions e.g. pause it while you are leaving wifi area to save cellular data and try to resume the download when wifi becomes available again after some time.

2. While downloading keep app in background, pause it and open other heavy ram usage apps to boot it out of memory then reopen app to check if video is still there in downloads list and whether it resumes the download when started again manually from downloads list.

[ABJ4403]

2. While downloading keep app in background, pause it and open other heavy ram usage apps to boot it out of memory then reopen app to check if video is still there in downloads list and whether it resumes the download when started again manually from downloads list.

Does am kill-all count? Bcz i'd rather do that, tho i have 2nd device that has 2GB RAM and filled up so quick when i load up a game, so i could try thatvas well

[TobiGr]

I tested this multiple times and did not run into new issues. Changes LGTM.

[Isira-Seneviratne]

The changes look good to me as well.