[gtk] (22 commits) ...Merge branch 'wip/baedert/single-node-window' into 'master'

[Timm Bäder <baedert src gnome org>]

Summary of changes:

  5b77d3f... widget: Remove GtkWindow special case in create_render_node (*)
  077692a... window: Remove custom snapshot() implementation (*)
  2579f66... window: Don't care about shadow in size_allocate() (*)
  2c2092e... window: Don't care about shadow in measure() (*)
  e1007e6... window: Remove decoration node (*)
  388733f... testsuite: Remove window decoration nodes from reference re (*)
  5ebabd7... Call all window subclasses "window" (*)
  b41838a... Window: Remove extra_input_region API (*)
  8e8e869... inspector: Don't offset layout overlay too much (*)
  a5e7e72... inspector: Fix overlay coordinates (*)
  7659d8a... window: Set overflow to HIDDEN (*)
  8c884e9... window: Fix get_surface_transform() (*)
  7eec162... window: Avoid using GtkStyleContext in subtract_decoration_ (*)
  1318370... window: Fix computing the opaque region (*)
  ec594f8... window: Rewrite edge region detection (*)
  018efdb... window: Inline gtk_window_configure() into only caller (*)
  dfbcd47... window: Fix the surface coordinates everywhere (*)
  5c458e3... Adwaita: style updates for new window node hierarchy (*)
  ee9d99c... update documentation for new style classes and node names (*)
  9cc6ddf... window: Create default titlebar directly in realize (*)
  22e7d11... window: Use GtkNative's check_resize everywhere (*)
  7d57f97... Merge branch 'wip/baedert/single-node-window' into 'master'

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