Column view: Fix indentation problem when org-indent-mode is active

* lisp/org-colview.el (org-columns-display-here): Use overlays to
overrule line prefix properties during column view.

lisp/org-colview.el

@@ -228,7 +228,9 @@ This is the compiled version of the format.")
        (overlay-put ov 'org-columns-value (cdr ass))
        (overlay-put ov 'org-columns-value-modified modval)
        (overlay-put ov 'org-columns-pom pom)
-       (overlay-put ov 'org-columns-format f))
+       (overlay-put ov 'org-columns-format f)
+       (overlay-put ov 'line-prefix "")
+       (overlay-put ov 'wrap-prefix ""))
       (if (or (not (char-after beg))
 	      (equal (char-after beg) ?\n))
 	  (let ((inhibit-read-only t))
@@ -241,6 +243,8 @@ This is the compiled version of the format.")
        (overlay-put ov 'invisible t)
        (overlay-put ov 'keymap org-columns-map)
        (overlay-put ov 'intangible t)
+       (overlay-put ov 'line-prefix "")
+       (overlay-put ov 'wrap-prefix "")
        (push ov org-columns-overlays)
        (setq ov (make-overlay (1- (point-at-eol)) (1+ (point-at-eol))))
        (overlay-put ov 'keymap org-columns-map)