[gnome-software/gnome-3-30] (12 commits) ...packagekit refresh: Avoid re-downloading metadata for gs_plugin_download()

[Kalev Lember <klember src gnome org>]

Summary of changes:

  1025489... packagekit refresh: Don't implement gs_plugin_update (*)
  da4b58c... update monitor: trivial: Rename a variable (*)
  09c1278... update monitor: Notify about offline updates after they are (*)
  f6a2913... updates page: trivial: Rename a variable (*)
  5bba02d... updates section: Split up offline update downloading and in (*)
  a305aa5... systemd updates: Fix various issues with refine (*)
  dfa67d6... app row: Don't show size for offline updatable apps (*)
  e47c7ac... Use background tasks for update monitor initiated packageki (*)
  05c1c2a... shell: Tweak which errors messages are shown for the DOWNLO (*)
  d943e09... plugin loader: Reset related apps progress when a job finis (*)
  6b68087... css: Style progress button so that it starts with 0% of pro (*)
  ce2942b... packagekit refresh: Avoid re-downloading metadata for gs_pl (*)

(*) This commit already existed in another branch; no separate mail sent