[mutter] monitor-config-manager: Fix layout size with scaled mirroring

[Marge Bot <marge-bot src gnome org>]

commit 5fb4a2c286af90788ff10457a395f606387b914e
Author: Jonas Ådahl <jadahl gmail com>
Date:   Thu Jun 23 12:42:55 2022 +0200

    monitor-config-manager: Fix layout size with scaled mirroring
    
    The dimension of the logical monitor layout was not scaled according to
    the scale, meaning generated mirror monitor configurations were broken.
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2479>

 src/backends/meta-monitor-config-manager.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/src/backends/meta-monitor-config-manager.c b/src/backends/meta-monitor-config-manager.c
index eafc6c6b69..84ea04faa8 100644
--- a/src/backends/meta-monitor-config-manager.c
+++ b/src/backends/meta-monitor-config-manager.c
@@ -1180,6 +1180,7 @@ create_for_switch_config_all_mirror (MetaMonitorConfigManager *config_manager)
   GList *monitors;
   GList *l;
   MetaMonitorsConfig *monitors_config;
+  int width, height;
 
   layout_mode = meta_monitor_manager_get_default_layout_mode (monitor_manager);
   monitors = meta_monitor_manager_get_monitors (monitor_manager);
@@ -1261,13 +1262,17 @@ create_for_switch_config_all_mirror (MetaMonitorConfigManager *config_manager)
       monitor_configs = g_list_prepend (monitor_configs, create_monitor_config (monitor, mode));
     }
 
+  scale_logical_monitor_width (layout_mode, best_scale,
+                               common_mode_w, common_mode_h,
+                               &width, &height);
+
   logical_monitor_config = g_new0 (MetaLogicalMonitorConfig, 1);
   *logical_monitor_config = (MetaLogicalMonitorConfig) {
     .layout = (MetaRectangle) {
       .x = 0,
       .y = 0,
-      .width = common_mode_w,
-      .height = common_mode_h
+      .width = width,
+      .height = height
     },
     .scale = best_scale,
     .monitor_configs = monitor_configs