Use `org-flag-subtree' instead of `outline-hide-subtree'

* lisp/org-agenda.el (org-agenda-show-1):
* lisp/org-archive.el (org-archive-to-archive-sibling):
* lisp/org-crypt.el (org-encrypt-entry):
* lisp/org-feed.el (org-feed-update):
* lisp/org.el (org-set-visibility-according-to-property):
(org-move-subtree-down):
(org-paste-subtree):
(org-yank-generic):
* testing/lisp/test-org-inlinetask.el (test-org-inlinetask/folding-directly-consecutive-tasks/1): Use `org-flag-subtree' instead of `outline-hide-subtree'.

`outline-hide-subtree' leaves overlays on top of white spaces,
particularly at the end of the buffer. `org-flag-subtree' does not.

lisp/org-agenda.el

@@ -8766,7 +8766,7 @@ if it was hidden in the outline."
     (set-window-start (selected-window) (point-at-bol))
     (cond
      ((= more 0)
-      (outline-hide-subtree)
+      (org-flag-subtree t)
       (save-excursion
 	(org-back-to-heading)
 	(run-hook-with-args 'org-cycle-hook 'folded))

lisp/org-archive.el

@@ -450,7 +450,7 @@ Archiving time is retained in the ARCHIVE_TIME node property."
 	 (format-time-string
 	  (substring (cdr org-time-stamp-formats) 1 -1)))
 	(outline-up-heading 1 t)
-	(outline-hide-subtree)
+	(org-flag-subtree t)
 	(org-cycle-show-empty-lines 'folded)
 	(when org-provide-todo-statistics
 	  ;; Update TODO statistics of parent.

lisp/org-crypt.el

@@ -190,7 +190,7 @@ See `org-crypt-disable-auto-save'."
 	     (error (insert contents) (error (nth 1 err)))))
 	 (when folded
 	   (goto-char start-heading)
-	   (outline-hide-subtree))
+	   (org-flag-subtree t))
 	 nil)))))
 
 (defun org-decrypt-entry ()

lisp/org-feed.el

@@ -412,7 +412,7 @@ it can be a list structured like an entry in `org-feed-alist'."
 
 	  ;; Normalize the visibility of the inbox tree
 	  (goto-char inbox-pos)
-	  (outline-hide-subtree)
+	  (org-flag-subtree t)
 	  (org-show-children)
 
 	  ;; Hooks and messages

lisp/org.el

@@ -6480,11 +6480,11 @@ With a numeric prefix, show all headlines up to that level."
 	  (if (not (org-at-property-p)) (outline-next-heading)
 	    (save-excursion
 	      (org-back-to-heading t)
-	      (outline-hide-subtree)
+	      (org-flag-subtree t)
 	      (org-reveal)
 	      (pcase state
 		("folded"
-		 (outline-hide-subtree))
+		 (org-flag-subtree t))
 		("children"
 		 (org-show-hidden-entry)
 		 (org-show-children))
@@ -7490,7 +7490,7 @@ case."
      (org-skip-whitespace)
      (move-marker ins-point nil)
      (if folded
-	 (outline-hide-subtree)
+	 (org-flag-subtree t)
        (org-show-entry)
        (org-show-children))
      (org-clean-visibility-after-subtree-move)
@@ -7656,7 +7656,7 @@ When REMOVE is non-nil, remove the subtree from the clipboard."
 		(equal org-subtree-clip (current-kill 0))
 		org-subtree-clip-folded)
        ;; The tree was folded before it was killed/copied
-       (outline-hide-subtree))
+       (org-flag-subtree t))
      (when for-yank (goto-char newend))
      (when remove (pop kill-ring)))))
 
@@ -20365,7 +20365,7 @@ interactive command with similar behavior."
 	     (or (looking-at org-outline-regexp)
 		 (re-search-forward org-outline-regexp-bol end t))
 	     (while (and (< (point) end) (looking-at org-outline-regexp))
-	       (outline-hide-subtree)
+	       (org-flag-subtree t)
 	       (org-cycle-show-empty-lines 'folded)
 	       (condition-case nil
 		   (outline-forward-same-level 1)

testing/lisp/test-org-inlinetask.el

@@ -148,7 +148,7 @@ p4
 *************** END
 
 "
-     (outline-hide-subtree)
+     (org-flag-subtree t)
      (org-cycle)
      (and
       (not (invisible-p (1- (search-forward "p1"))))