Replace kill-this-buffer with kill-current-buffer

As per the documentation for kill-this-buffer, it should only be invoked
from the menu and behaves unpredictably when invoked programmatically.

core/autoload/buffers.el

@@ -250,10 +250,10 @@ regex PATTERN. Returns the number of killed buffers."
 
 ;;;###autoload
 (defun doom*switch-to-fallback-buffer-maybe (orig-fn)
-  "Advice for `kill-this-buffer'. If in a dedicated window, delete it. If there
+  "Advice for `kill-current-buffer'. If in a dedicated window, delete it. If there
 are no real buffers left OR if all remaining buffers are visible in other
 windows, switch to `doom-fallback-buffer'. Otherwise, delegate to original
-`kill-this-buffer'."
+`kill-current-buffer'."
   (let ((buf (current-buffer)))
     (cond ((window-dedicated-p)
            (delete-window))

core/autoload/debug.el

@@ -190,7 +190,7 @@ markdown and copies it to your clipboard, ready to be pasted into bug reports!"
     (define-key map (kbd "C-c C-d") #'doom--run-vanilla-doom)
     (define-key map (kbd "C-c C-p") #'doom--run-vanilla-doom+)
     (define-key map (kbd "C-c C-f") #'doom--run-full-doom)
-    (define-key map (kbd "C-c C-k") #'kill-this-buffer)
+    (define-key map (kbd "C-c C-k") #'kill-current-buffer)
     map))
 
 (define-derived-mode doom-sandbox-emacs-lisp-mode emacs-lisp-mode "Sandbox Elisp"
@@ -289,7 +289,7 @@ will be automatically appended to the result."
                        backtrace)
              "")))
         (local-set-key (kbd "C-c C-c") #'doom--report-bug)
-        (local-set-key (kbd "C-c C-k") #'kill-this-buffer)
+        (local-set-key (kbd "C-c C-k") #'kill-current-buffer)
         (setq header-line-format "C-c C-c to submit / C-c C-k to close")
         ;;
         (narrow-to-region (point-min) pos)

core/autoload/files.el

@@ -187,7 +187,7 @@ file if it exists, without confirmation."
              (when-let* ((dest (doom--copy-file old-path new-path force-p)))
                (when (file-exists-p old-path)
                  (delete-file old-path))
-               (kill-this-buffer)
+               (kill-current-buffer)
                (doom--forget-file old-path new-path)
                (doom--update-file new-path)
                (find-file new-path)

core/autoload/ui.el

@@ -178,7 +178,7 @@ Inspired from http://demonastery.org/2013/04/emacs-evil-narrow-region/"
              (setq doom--buffer-narrowed-origin old-buf)))
          (narrow-to-region beg end))
         (doom--buffer-narrowed-origin
-         (kill-this-buffer)
+         (kill-current-buffer)
          (switch-to-buffer doom--buffer-narrowed-origin)
          (setq doom--buffer-narrowed-origin nil))
         (t