[gnome-shell] (17 commits) Non-fast-forward update to branch wip/rstrode/login-screen-extensions

[Ray Strode <halfline src gnome org>]

The branch 'wip/rstrode/login-screen-extensions' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  65b666b... extensionSystem: Allow extensions to run on the login scree
  ba966ca... sessionMode: Allow extensions at the login and unlock scree
  a1ce46b... sessionMode: Drop allowExtensions property

Commits added to the branch:

  3685cb1... Update Icelandic translation (*)
  2bcc6c0... st/icon: Ensure icons are updated if theme node is invalid (*)
  380d2db... inputMethod: Clear preeditStr before reset (*)
  7f77b6f... welcomeDialog: Fix title translation (*)
  c0b8938... Update Croatian translation (*)
  82e16a2... Add screen protect status icons (*)
  a3dcdaa... screenshot: Unrestrict PickColor (*)
  4d1ce0d... notificationDaemon: Fix sound-file support (*)
  5d5bfe4... unlockDialog: Don't create AuthDialog just to finish it (*)
  ceee53a... unlockDialog: Properly reset auth prompt when showing it (*)
  4e5ddc5... ci: Install mutter again on coverity job (*)
  c1c0b34... Updated Czech translation (*)
  ddb6276... st/password-entry: Fix crash when DConf changes after StEnt (*)
  d9fdae4... extensionSystem: Get rid of _enabled boolean optimization
  67beed2... extensionSystem: Allow extensions to run on the login scree
  1198653... sessionMode: Allow extensions at the login and unlock scree
  d28f3cf... sessionMode: Drop allowExtensions property

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