backends: Allow integrated tablet devices to cycle outputs

The work at https://gitlab.gnome.org/GNOME/gnome-control-center/issues/239
intended to make integrated devices optionally mappable to other outputs
(in order to allow fix mishandling from our heuristics, or to quickly reach
things in other monitor without changing devices).

This was missed in that plan, we do allow cycling outputs, but we still did
prevent it from doing anything for integrated devices. Fix that, and change
output cycling so we don't allow a "NULL" EDID for integrated devices, this
makes those go through the MetaInputMapper (resulting in one output listed
twice), instead of mapping to the full stage.

Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1186

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1201

src/backends/meta-input-settings.c

@@ -2179,6 +2179,7 @@ meta_input_settings_get_pad_button_action (MetaInputSettings   *input_settings,
 
 static gboolean
 cycle_logical_monitors (MetaInputSettings   *settings,
+                        gboolean             skip_all_monitors,
                         MetaLogicalMonitor  *current_logical_monitor,
                         MetaLogicalMonitor **next_logical_monitor)
 {
@@ -2188,7 +2189,8 @@ cycle_logical_monitors (MetaInputSettings   *settings,
   GList *logical_monitors;
 
   /* We cycle between:
-   * - the span of all monitors (current_output = NULL)
+   * - the span of all monitors (current_output = NULL), only for
+   *   non-integrated devices.
    * - each monitor individually.
    */
 
@@ -2206,6 +2208,8 @@ cycle_logical_monitors (MetaInputSettings   *settings,
       l = g_list_find (logical_monitors, current_logical_monitor);
       if (l->next)
         *next_logical_monitor = l->next->data;
+      else if (skip_all_monitors)
+        *next_logical_monitor = logical_monitors->data;
       else
         *next_logical_monitor = NULL;
     }
@@ -2221,6 +2225,7 @@ meta_input_settings_cycle_tablet_output (MetaInputSettings  *input_settings,
   DeviceMappingInfo *info;
   MetaLogicalMonitor *logical_monitor = NULL;
   const gchar *edid[4] = { 0 }, *pretty_name = NULL;
+  gboolean is_integrated_device = FALSE;
 #ifdef HAVE_LIBWACOM
   WacomDevice *wacom_device;
 #endif
@@ -2239,11 +2244,9 @@ meta_input_settings_cycle_tablet_output (MetaInputSettings  *input_settings,
 
   if (wacom_device)
     {
-      /* Output rotation only makes sense on external tablets */
-      if (libwacom_get_integration_flags (wacom_device) != WACOM_DEVICE_INTEGRATED_NONE)
-        return;
-
       pretty_name = libwacom_get_name (wacom_device);
+      is_integrated_device =
+        libwacom_get_integration_flags (wacom_device) != WACOM_DEVICE_INTEGRATED_NONE;
     }
 #endif
 
@@ -2251,6 +2254,7 @@ meta_input_settings_cycle_tablet_output (MetaInputSettings  *input_settings,
                                     NULL, &logical_monitor);
 
   if (!cycle_logical_monitors (input_settings,
+                               is_integrated_device,
                                logical_monitor,
                                &logical_monitor))
     return;