Update packages/darkroom by merging its external subtree

diff --combined packages/darkroom/darkroom.el
index 45eaf9d96ea48d75e1e19dc8c930f5d8e7d36d0a,65424691247309068c33107eb9fab5110e3ac4b6..65424691247309068c33107eb9fab5110e3ac4b6
--- 1/packages/darkroom/darkroom.el
--- 2/darkroom.el
+++ b/packages/darkroom/darkroom.el
@@@ -319,6 -319,9 +319,9 @@@ With optional JUST-MARGINS, just set th
           ;; for clarity, don't do anything
           )))
  
+ (declare-function darkroom-tentative-mode "darkroom" t)
+ 
+ ;;;###autoload
  (define-minor-mode darkroom-mode
    "Remove visual distractions and focus on writing. When this
  mode is active, everything but the buffer's text is elided from
@@@ -341,6 -344,7 +344,7 @@@ screen. Text size is increased (displa
           (remove-hook 'window-configuration-change-hook 'darkroom--set-margins
                        t))))
  
+ ;;;###autoload
  (define-minor-mode darkroom-tentative-mode
    "Enters `darkroom-mode' when all other windows are deleted."
    nil " Room" darkroom-mode-map
@@@ -370,6 -374,5 +374,5 @@@
           (darkroom--leave))))
  
  
- 
  (provide 'darkroom)
  ;;; darkroom.el ends here