[gtk] (15 commits) ...Merge branch 'wip/baedert/for-master' into 'master'

[Matthias Clasen <matthiasc src gnome org>]

Summary of changes:

  69293db... builderparser: Only allocate subparser stack when needed (*)
  aec2fb9... builderparser: Keep properties in a GPtrArray (*)
  de6cd4f... builder: Use a GPtrArray when parsing signals (*)
  b1c8613... accessible: Fix memory leak if context is unset (*)
  872b46a... widget: Shorten get_halign() a bit (*)
  cb41b96... builderparser: Save finalizers in a GPtrArray (*)
  ec8614e... label: Fix a potential memory leak (*)
  650eed7... gl renderer: Properly y-flip non-offscreen children of roun (*)
  4d7a015... gl renderer: Don't reset offset when drawing offscreen (*)
  c305023... label: Refactor get_layout_location (*)
  934b91f... label: Remove unneeded NULL guards (*)
  d9f6b26... gl renderer: Use rect_contains_rect() copy (*)
  a394976... Add nullable annotations to GtkShortcutFunc (*)
  5ea3777... widget: Fix gtk_widget_class_add_binding() argument name (*)
  0088301... Merge branch 'wip/baedert/for-master' into 'master'

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