[gtk/gtk-3-24: 4/5] wayland: Add margin to saved size when restoring size

[Matthias Clasen <matthiasc src gnome org>]

commit 3b91c20eac6c1480af9f7ea3067e24132591fd6c
Author: Jonas Ådahl <jadahl gmail com>
Date:   Thu Apr 2 17:53:57 2020 +0200

    wayland: Add margin to saved size when restoring size
    
    We're normally going from a fixed size to a floating state when we're
    using the saved size, meaning we're practically always going towards a
    state where the shadow margin will non-empty. However, if we don't
    include any margin when creating a new configure request, we'll end up
    resizing to a slightly smaller size as gtk will cut off the margin from
    the configure request when changing the window widget size.
    
    This wasn't visible when e.g. going from maximized to floating, as we'd
    add the shadow margin at a later point, which would effectively "grow"
    the widnow size, but when we're going from tiled to floating, we both
    start and end with a non-empty shadow margin, meaning we'd shrink ever
    so slightly every time going between tiled and floating.

 gdk/wayland/gdkwindow-wayland.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)
---
diff --git a/gdk/wayland/gdkwindow-wayland.c b/gdk/wayland/gdkwindow-wayland.c
index 9c9d311abf..0ba53e75e2 100644
--- a/gdk/wayland/gdkwindow-wayland.c
+++ b/gdk/wayland/gdkwindow-wayland.c
@@ -1580,6 +1580,8 @@ gdk_wayland_window_handle_configure (GdkWindow *window,
   if (width > 0 && height > 0)
     {
       GdkWindowHints geometry_mask = impl->geometry_mask;
+      int configure_width;
+      int configure_height;
 
       /* Ignore size increments for maximized/fullscreen windows */
       if (fixed_size)
@@ -1598,7 +1600,20 @@ gdk_wayland_window_handle_configure (GdkWindow *window,
           _gdk_wayland_window_save_size (window);
         }
 
-      gdk_wayland_window_configure (window, width, height, impl->scale);
+      if (saved_size)
+        {
+          configure_width = width + impl->margin_left + impl->margin_right;
+          configure_height = height + impl->margin_top + impl->margin_bottom;
+        }
+      else
+        {
+          configure_width = width;
+          configure_height = height;
+        }
+      gdk_wayland_window_configure (window,
+                                    configure_width,
+                                    configure_height,
+                                    impl->scale);
     }
   else
     {