Fix crash when using the LC_CTYPE=eo.ut8 on X11.

The window title setting implementation wasn't checking an error return.
It now does so, logging the error if it fails.

In this case, it fails for this locale. I have not investigated whether
this can be made to work, but at least it doesn't segfault/hang etc.

Fixes #1651

Author: SiegeLordEx

src/x/xdisplay.c

@@ -1216,13 +1216,21 @@ static void xdpy_set_window_title_default(ALLEGRO_DISPLAY *display, const char *
       Atom _NET_WM_NAME = XInternAtom(system->x11display, "_NET_WM_NAME", False);
       char *list[1] = { (char *) title };
       XTextProperty property;
-
-      Xutf8TextListToTextProperty(system->x11display, list, 1, XUTF8StringStyle,
+      int status = Xutf8TextListToTextProperty(system->x11display, list, 1, XUTF8StringStyle,
          &property);
-      XSetTextProperty(system->x11display, glx->window, &property, WM_NAME);
-      XSetTextProperty(system->x11display, glx->window, &property, _NET_WM_NAME);
-      XSetTextProperty(system->x11display, glx->window, &property, XA_WM_NAME);
-      XFree(property.value);
+
+      if (status == Success) {
+         XSetTextProperty(system->x11display, glx->window, &property, WM_NAME);
+         XSetTextProperty(system->x11display, glx->window, &property, _NET_WM_NAME);
+         XSetTextProperty(system->x11display, glx->window, &property, XA_WM_NAME);
+         XFree(property.value);
+      }
+      else if (status == XLocaleNotSupported) {
+         ALLEGRO_WARN("Couldn't set window title. Xutf8TextListToTextProperty returned XLocaleNotSupported.\n");
+      }
+      else {
+         ALLEGRO_WARN("Couldn't set window title. Xutf8TextListToTextProperty returned: %d\n", status);
+      }
    }
    {
       XClassHint *hint = XAllocClassHint();