bug#31919: 26.1.50; Lisp Debugger doesn't work when at stack limit

[Gemini Lasswell]

Is this patch OK for emacs-26?

> Here's a patch to give the Debugger and cl-print more stack space
> during the recursive edit:
>
>>From d044dc12a2b5794bd1155fd5b7ff7adb3bc8841d Mon Sep 17 00:00:00 2001
> From: Gemini Lasswell <gazally@runbox.com>
> Date: Wed, 20 Jun 2018 13:58:33 -0700
> Subject: [PATCH] Increase max-lisp-eval-depth adjustment while in debugger
>
> * src/eval.c (call_debugger): Increase the amount of extra stack
> depth given to the debugger to allow it to call cl-print.
> ---
>  src/eval.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/src/eval.c b/src/eval.c
> index ca1eb84ff3..f9bc13ade7 100644
> --- a/src/eval.c
> +++ b/src/eval.c
> @@ -282,8 +282,8 @@ call_debugger (Lisp_Object arg)
>    /* Do not allow max_specpdl_size less than actual depth (Bug#16603).  */
>    EMACS_INT old_max = max (max_specpdl_size, count);
>  
> -  if (lisp_eval_depth + 40 > max_lisp_eval_depth)
> -    max_lisp_eval_depth = lisp_eval_depth + 40;
> +  if (lisp_eval_depth + 80 > max_lisp_eval_depth)
> +    max_lisp_eval_depth = lisp_eval_depth + 80;
>  
>    /* While debugging Bug#16603, previous value of 100 was found
>       too small to avoid specpdl overflow in the debugger itself.  */