[clutter/msvc-support-master] (11 commits) ...Merge branch 'master' into msvc-support-master

[Chun-wei Fan <fanchunwei src gnome org>]

Summary of changes:

  c607382... Updated Spanish translation (*)
  5dbc00e... box-layout: Plug memory leaks (*)
  25b7b30... Add clutter_unicode_to_keyval function (*)
  6d974f2... Mark clutter_state_set_key() source_state_name as nullable (*)
  389d247... texture: Drop G_MUTEX_INIT (*)
  3690ddc... Drop g_thread_init() (*)
  32b8217... Use a static mutex for the default Clutter lock (*)
  7e3a75c... Deprecate clutter_threads_init() (*)
  b5109e8... animation: Use the timeline's new-frame signal (*)
  58fec63... Updated Lithuanian translation (*)
  1cf7128... Merge branch 'master' into msvc-support-master

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