[mutter] window/wayland: Don't always use constrained size when unfullscreening

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 59bf1f48380feb46e42863d4b4fa121261f09146
Author: Jonas Ådahl <jadahl gmail com>
Date:   Thu Jun 13 10:35:35 2019 +0200

    window/wayland: Don't always use constrained size when unfullscreening
    
    When we're unfullscreening, we might be returning to a window state that
    has its size either managed by constraints (tiled, maximized), or not
    (floating). Lets just pass the configure size 0x0 when we're not using
    constrained sizes (i.e. the window going from being fullscreen to not
    maximized) and let the application decide how to size itself.
    
    Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/638
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/621

 src/core/window-private.h         | 7 ++++---
 src/core/window.c                 | 3 ++-
 src/wayland/meta-window-wayland.c | 7 +++++++
 3 files changed, 13 insertions(+), 4 deletions(-)
---
diff --git a/src/core/window-private.h b/src/core/window-private.h
index 6a27949c8..0c71152a4 100644
--- a/src/core/window-private.h
+++ b/src/core/window-private.h
@@ -81,9 +81,10 @@ typedef enum
   META_MOVE_RESIZE_WAYLAND_RESIZE = 1 << 4,
   META_MOVE_RESIZE_STATE_CHANGED = 1 << 5,
   META_MOVE_RESIZE_UNMAXIMIZE = 1 << 6,
-  META_MOVE_RESIZE_FORCE_MOVE = 1 << 7,
-  META_MOVE_RESIZE_WAYLAND_STATE_CHANGED = 1 << 8,
-  META_MOVE_RESIZE_FORCE_UPDATE_MONITOR = 1 << 9,
+  META_MOVE_RESIZE_UNFULLSCREEN = 1 << 7,
+  META_MOVE_RESIZE_FORCE_MOVE = 1 << 8,
+  META_MOVE_RESIZE_WAYLAND_STATE_CHANGED = 1 << 9,
+  META_MOVE_RESIZE_FORCE_UPDATE_MONITOR = 1 << 10,
 } MetaMoveResizeFlags;
 
 typedef enum
diff --git a/src/core/window.c b/src/core/window.c
index c1179c6ad..1b36ff7b9 100644
--- a/src/core/window.c
+++ b/src/core/window.c
@@ -3561,7 +3561,8 @@ meta_window_unmake_fullscreen (MetaWindow  *window)
       meta_window_move_resize_internal (window,
                                         (META_MOVE_RESIZE_MOVE_ACTION |
                                          META_MOVE_RESIZE_RESIZE_ACTION |
-                                         META_MOVE_RESIZE_STATE_CHANGED),
+                                         META_MOVE_RESIZE_STATE_CHANGED |
+                                         META_MOVE_RESIZE_UNFULLSCREEN),
                                         NorthWestGravity,
                                         target_rect);
 
diff --git a/src/wayland/meta-window-wayland.c b/src/wayland/meta-window-wayland.c
index db6476f19..d72b3bbc1 100644
--- a/src/wayland/meta-window-wayland.c
+++ b/src/wayland/meta-window-wayland.c
@@ -224,6 +224,13 @@ meta_window_wayland_move_resize_internal (MetaWindow                *window,
       configured_width = 0;
       configured_height = 0;
     }
+  else if (flags & META_MOVE_RESIZE_UNFULLSCREEN &&
+           !meta_window_get_maximized (window) &&
+           meta_window_get_tile_mode (window) == META_TILE_NONE)
+    {
+      configured_width = 0;
+      configured_height = 0;
+    }
   else
     {
       configured_width = constrained_rect.width / geometry_scale;