[mutter] wayland/xdg-shell: Add toplevel tile state support

[Jonas Ådahl <jadahl src gnome org>]

commit 4673eeaf5fe59f2ba4c1af945924347bcaac782e
Author: Jonas Ådahl <jadahl gmail com>
Date:   Wed Oct 24 14:45:11 2018 +0200

    wayland/xdg-shell: Add toplevel tile state support
    
    The second version of xdg_wm_base added toplevel tile states (top,
    right, bottom, left), so lets communicate that.

 src/wayland/meta-wayland-versions.h  |  2 +-
 src/wayland/meta-wayland-xdg-shell.c | 29 ++++++++++++++++++++++-------
 2 files changed, 23 insertions(+), 8 deletions(-)
---
diff --git a/src/wayland/meta-wayland-versions.h b/src/wayland/meta-wayland-versions.h
index 63ca9b0d6..9e1139a91 100644
--- a/src/wayland/meta-wayland-versions.h
+++ b/src/wayland/meta-wayland-versions.h
@@ -37,7 +37,7 @@
 /* Global/master objects (version exported by wl_registry and negotiated through bind) */
 #define META_WL_COMPOSITOR_VERSION          4
 #define META_WL_DATA_DEVICE_MANAGER_VERSION 3
-#define META_XDG_WM_BASE_VERSION            1
+#define META_XDG_WM_BASE_VERSION            2
 #define META_ZXDG_SHELL_V6_VERSION          1
 #define META_WL_SHELL_VERSION               1
 #define META_WL_SEAT_VERSION                5
diff --git a/src/wayland/meta-wayland-xdg-shell.c b/src/wayland/meta-wayland-xdg-shell.c
index 3e5a18e57..9e1d86bd5 100644
--- a/src/wayland/meta-wayland-xdg-shell.c
+++ b/src/wayland/meta-wayland-xdg-shell.c
@@ -583,9 +583,15 @@ add_state_value (struct wl_array         *states,
 }
 
 static void
-fill_states (struct wl_array *states,
-             MetaWindow      *window)
+fill_states (MetaWaylandXdgToplevel *xdg_toplevel,
+             struct wl_array        *states)
 {
+  MetaWaylandSurfaceRole *surface_role =
+    META_WAYLAND_SURFACE_ROLE (xdg_toplevel);
+  MetaWaylandSurface *surface =
+    meta_wayland_surface_role_get_surface (surface_role);
+  MetaWindow *window = surface->window;
+
   if (META_WINDOW_MAXIMIZED (window))
     add_state_value (states, XDG_TOPLEVEL_STATE_MAXIMIZED);
   if (meta_window_is_fullscreen (window))
@@ -594,6 +600,19 @@ fill_states (struct wl_array *states,
     add_state_value (states, XDG_TOPLEVEL_STATE_RESIZING);
   if (meta_window_appears_focused (window))
     add_state_value (states, XDG_TOPLEVEL_STATE_ACTIVATED);
+
+  if (wl_resource_get_version (xdg_toplevel->resource) >=
+      XDG_TOPLEVEL_STATE_TILED_LEFT_SINCE_VERSION)
+    {
+      if (window->edge_constraints.top != META_EDGE_CONSTRAINT_NONE)
+        add_state_value (states, XDG_TOPLEVEL_STATE_TILED_TOP);
+      if (window->edge_constraints.right != META_EDGE_CONSTRAINT_NONE)
+        add_state_value (states, XDG_TOPLEVEL_STATE_TILED_RIGHT);
+      if (window->edge_constraints.bottom != META_EDGE_CONSTRAINT_NONE)
+        add_state_value (states, XDG_TOPLEVEL_STATE_TILED_BOTTOM);
+      if (window->edge_constraints.left != META_EDGE_CONSTRAINT_NONE)
+        add_state_value (states, XDG_TOPLEVEL_STATE_TILED_LEFT);
+    }
 }
 
 static void
@@ -603,15 +622,11 @@ meta_wayland_xdg_toplevel_send_configure (MetaWaylandXdgToplevel *xdg_toplevel,
                                           MetaWaylandSerial      *sent_serial)
 {
   MetaWaylandXdgSurface *xdg_surface = META_WAYLAND_XDG_SURFACE (xdg_toplevel);
-  MetaWaylandSurfaceRole *surface_role =
-    META_WAYLAND_SURFACE_ROLE (xdg_toplevel);
-  MetaWaylandSurface *surface =
-    meta_wayland_surface_role_get_surface (surface_role);
   struct wl_array states;
   uint32_t serial;
 
   wl_array_init (&states);
-  fill_states (&states, surface->window);
+  fill_states (xdg_toplevel, &states);
 
   xdg_toplevel_send_configure (xdg_toplevel->resource,
                                new_width, new_height,