[gnome-shell] (14 commits) Non-fast-forward update to branch cherry-pick-551e8278-2

[Florian Müllner <fmuellner src gnome org>]

The branch 'cherry-pick-551e8278-2' 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:

  6b45bb0... keyboard: Do not call KeyboardManager.holdKeyboard() with s

Commits added to the branch:

  fa2ddcc... dnd: Repick target actor if destroyed mid iteration (*)
  b29e243... st: Avoid integer overflow on unpremultiply (*)
  128a501... StTextureCache: use right event to detect file changes (*)
  d53bd98... StWidget: don't forget to invalidate the paint state if not (*)
  420c1cb... dash: destroy items's child before tooltip (*)
  e7463e3... notificationDaemon: support file:// or icon theme names for (*)
  1e92935... panel: Also ignore hidden windows for proximity (*)
  219118e... viewSelector: Don't unfocus other modals on reset (*)
  36f9dcd... endSessionDialog: squash "reference to undefined property"  (*)
  06c6ecc... workspacesView: initialize self._restackedNotifyId (*)
  8111286... messageTray: Disable unredirection while showing banners (*)
  5e7a7e3... messageTray: Re-enable unredirection when banner is destroy (*)
  a732943... altSwitcher: Fix error when all alternatives are disabled (*)
  1b28cdf... keyboard: Do not call KeyboardManager.holdKeyboard() with s

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