[gnome-shell] (4 commits) ...theme: Handle fallback app icons in notifications

[Florian Müllner <fmuellner src gnome org>]

Summary of changes:

  6f79473... texture-cache: Load bound surfaces into StWidgets (*)
  d86d3bb... texture-cache: Fall back to actor size for bound textures (*)
  4f65283... app: Set styleclass on fallback app icons (*)
  d4202e7... theme: Handle fallback app icons in notifications (*)

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