D26720: Cache single image wallpapers locally

[Nathaniel Graham]

ngraham created this revision.
ngraham added a reviewer: Plasma.
Herald added a project: Plasma.
Herald added a subscriber: plasma-devel.
ngraham requested review of this revision.

REVISION SUMMARY
  Right now, if the user sets a wallpaper and it disappears on disk, the next time Plasma
  is restarted, the wallpaper will be reset to the default, which is probably not what
  the user expected.
  
  This patch caches the wallpaper locally every time the user specifically changes it.
  Thereafter, if the path to the original wallpaper becomes invalid, Plasma will fall
  back to reading the wallpaper from the cache.
  
  BUG: 399905
  FIXED-IN; 5.18.0

TEST PLAN
  - Set wallpaper to some image on disk
  - Delete or rename that file
  - Restart plasmashell
  
  User-specified image is retained, rather than being replaced with the default wallpaper.
  
  No changes to slideshows or other wallpaper plugins.

REPOSITORY
  R120 Plasma Workspace

BRANCH
  wallpaper-cache (branched from Plasma/5.18)

REVISION DETAIL
  https://phabricator.kde.org/D26720

AFFECTED FILES
  wallpapers/image/image.cpp
  wallpapers/image/image.h

To: ngraham, #plasma
Cc: filipf, plasma-devel, LeGast00n, The-Feren-OS-Dev, jraleigh, zachus, fbampaloukas, GB_2, ragreen, ZrenBot, ngraham, alexeymin, himcesjf, lesliezhai, ali-mohamed, jensreuterberg, abetts, sebas, apol, ahiemstra, mart
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.kde.org/pipermail/plasma-devel/attachments/20200116/defa0384/attachment.html>