Rewrite doom-real-buffer-p; require first arg

Because of how widely used this function is, I'd rather it be as
explicit as possible to avoid bugs and to make it faster.

core/autoload/buffers.el

@@ -93,7 +93,7 @@ If no project is active, return all buffers."
   (cl-remove-if-not #'doom-real-buffer-p (or buffer-list (doom-buffer-list))))
 
 ;;;###autoload
-(defun doom-real-buffer-p (&optional buffer-or-name)
+(defun doom-real-buffer-p (buffer-or-name)
   "Returns t if BUFFER-OR-NAME is a 'real' buffer.
 
 A real buffer is a useful buffer; a first class citizen in Doom. Real ones
@@ -110,7 +110,10 @@ The exact criteria for a real buffer is:
      non-nil.
 
 If BUFFER-OR-NAME is omitted or nil, the current buffer is tested."
-  (when-let* ((buf (ignore-errors (window-normalize-buffer buffer-or-name))))
+  (or (bufferp buffer-or-name)
+      (stringp buffer-or-name)
+      (signal 'wrong-type-argument (list '(bufferp stringp) buffer-or-name)))
+  (when-let* ((buf (get-buffer buffer-or-name)))
     (and (not (doom-temp-buffer-p buf))
          (or (buffer-local-value 'doom-real-buffer-p buf)
              (run-hook-with-args-until-success 'doom-real-buffer-functions buf)

modules/feature/workspaces/autoload/workspaces.el

@@ -524,7 +524,7 @@ created."
       (if (not (persp-frame-list-without-daemon))
           (+workspace-switch +workspaces-main t)
         (+workspace-switch (format "#%s" (+workspace--generate-id)) t)
-        (unless (doom-real-buffer-p)
+        (unless (doom-real-buffer-p (current-buffer))
           (switch-to-buffer (doom-fallback-buffer)))
         (set-frame-parameter frame 'workspace (+workspace-current-name))
         ;; ensure every buffer has a buffer-predicate