emacs-27 3196fd4: Avoid crashes when a theme is loaded with one frame suspended

[Eli Zaretskii]

branch: emacs-27
commit 3196fd44c36a5ce6789382f74442c461d9264471
Author: Eli Zaretskii <eliz@gnu.org>
Commit: Eli Zaretskii <eliz@gnu.org>

    Avoid crashes when a theme is loaded with one frame suspended
    
    * src/xfaces.c (load_color2, Fcolor_distance): Don't try to call
    the frame's defined_color_hook if the frame is suspended.
    (Bug#43886)
---
 src/xfaces.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/xfaces.c b/src/xfaces.c
index 66d6c34..fab29ef 100644
--- a/src/xfaces.c
+++ b/src/xfaces.c
@@ -1059,6 +1059,13 @@ static unsigned long
 load_color2 (struct frame *f, struct face *face, Lisp_Object name,
              enum lface_attribute_index target_index, Emacs_Color *color)
 {
+  if (FRAME_TERMINAL (f)->defined_color_hook == NULL)
+    {
+      Lisp_Object frame;
+      XSETFRAME (frame, f);
+      signal_error ("Unable to load colors for suspended TTY frame", frame);
+    }
+
   eassert (STRINGP (name));
   eassert (target_index == LFACE_FOREGROUND_INDEX
           || target_index == LFACE_BACKGROUND_INDEX
@@ -4391,6 +4398,9 @@ two lists of the form (RED GREEN BLUE) aforementioned. */)
   struct frame *f = decode_live_frame (frame);
   Emacs_Color cdef1, cdef2;
 
+  if (FRAME_TERMINAL (f)->defined_color_hook == NULL)
+    signal_error ("Unable to validate colors for suspended TTY frame", frame);
+
   if (!(CONSP (color1) && parse_rgb_list (color1, &cdef1))
       && !(STRINGP (color1)
            && FRAME_TERMINAL (f)->defined_color_hook (f,