monitor-config: Update laptop heuristics to match GnomeRROutput

gnome-desktop's GnomeRROutput class has heuristics to classify a display
as builtin similar to our own[0]. The two heuristics don't quite match
though, so different core components can end up with a different view
on the current display configuration. Minimize that risk by adding a
couple of rules that bring the two heuristics closer together.

[0] https://git.gnome.org/browse/gnome-desktop/tree/libgnome-desktop/gnome-rr.c#n1674

https://bugzilla.gnome.org/show_bug.cgi?id=765267

src/backends/meta-monitor-config.c

@@ -913,6 +913,10 @@ key_is_laptop (MetaOutputKey *key)
 {
   /* FIXME: extend with better heuristics */
   return g_str_has_prefix (key->connector, "LVDS") ||
+    g_str_has_prefix (key->connector, "lvds") ||
+    g_str_has_prefix (key->connector, "Lvds") ||
+    g_str_has_prefix (key->connector, "LCD")  || /* some versions of fglrx, sigh */
+    g_str_has_prefix (key->connector, "DSI") ||
     g_str_has_prefix (key->connector, "eDP");
 }
 

src/backends/meta-monitor-manager.c

@@ -1466,6 +1466,7 @@ meta_output_is_laptop (MetaOutput *output)
     {
     case META_CONNECTOR_TYPE_eDP:
     case META_CONNECTOR_TYPE_LVDS:
+    case META_CONNECTOR_TYPE_DSI:
       return TRUE;
     default:
       return FALSE;