Introduce CLOCK_INTO_DRAWER property like the existing LOG_INTO_DRAWER

* lisp/org.el (defcustom org-log-into-drawer): correct typo
* lisp/org-clock.el: new function org-clock-into-drawer to change
  the location of clock events based on properties CLOCK_INTO_DRAWER
  or, as fallback, LOG_INTO_DRAWER, like it is already possible for
  state change logs.
* lisp/org-clock.el (org-clock-jump-to-current-clock): add statement
  to let clause to bind org-clock-into-drawer to result of function
  eval
* lisp/org-clock.el (org-clock-find-position): add statement
  to let clause to bind org-clock-into-drawer to result of function
  eval, change let to let* since the binding is used later in the
  same clause
* doc/org.texi: document that both CLOCK_INTO_DRAWER and
  LOG_INTO_DRAWER can be used to override the contents of variable
  org-clock-into-drawer (or if unset, org-log-into-drawer)
* doc/org.texi: @xref->@pxref

doc/org.texi

@@ -5759,11 +5759,15 @@ what to do with it.
 @table @kbd
 @orgcmd{C-c C-x C-i,org-clock-in}
 @vindex org-clock-into-drawer
+@cindex property, LOG_INTO_DRAWER
 Start the clock on the current item (clock-in).  This inserts the CLOCK
 keyword together with a timestamp.  If this is not the first clocking of
 this item, the multiple CLOCK lines will be wrapped into a
 @code{:LOGBOOK:} drawer (see also the variable
-@code{org-clock-into-drawer}).  When called with a @kbd{C-u} prefix argument,
+@code{org-clock-into-drawer}).  You can also overrule
+the setting of this variable for a subtree by setting a
+@code{CLOCK_INTO_DRAWER} or @code{LOG_INTO_DRAWER} property.
+When called with a @kbd{C-u} prefix argument,
 select the task from a list of recently clocked tasks.  With two @kbd{C-u
 C-u} prefixes, clock into the task at point and mark it as the default task.
 The default task will always be available when selecting a clocking task,
@@ -8950,7 +8954,7 @@ If the syntax for the label format conflicts with the language syntax, use a
 @code{-l} switch to change the format, for example @samp{#+BEGIN_SRC pascal
 -n -r -l "((%s))"}.  See also the variable @code{org-coderef-label-format}.
 
-HTML export also allows examples to be published as text areas (@xref{Text
+HTML export also allows examples to be published as text areas (@pxref{Text
 areas in HTML export}).
 
 Because the @code{#+BEGIN_...} and @code{#+END_...} patterns need to be added

lisp/org-clock.el

@@ -64,6 +64,22 @@ which see."
 	  (const :tag "Into LOGBOOK drawer" "LOGBOOK")
 	  (string :tag "Into Drawer named...")))
 
+(defun org-clock-into-drawer ()
+  "Return the value of `org-clock-into-drawer', but let properties overrule.
+If the current entry has or inherits a CLOCK_INTO_DRAWER
+property, it will be used instead of the default value; otherwise
+if the current entry has or inherits a LOG_INTO_DRAWER property,
+it will be used instead of the default value.
+The default is the value of the customizable variable `org-clock-into-drawer',
+which see."
+  (let ((p (org-entry-get nil "CLOCK_INTO_DRAWER" 'inherit))
+	(q (org-entry-get nil "LOG_INTO_DRAWER" 'inherit)))
+    (cond
+     ((or (not (or p q)) (equal p "nil") (equal q "nil")) org-clock-into-drawer)
+     ((or (equal p "t") (equal q "t")) "LOGBOOK")
+     ((not p) q)
+     (t p))))
+
 (defcustom org-clock-out-when-done t
   "When non-nil, clock will be stopped when the clocked entry is marked DONE.
 DONE here means any DONE-like state.
@@ -761,7 +777,8 @@ If necessary, clock-out of the currently active clock."
 
 (defun org-clock-jump-to-current-clock (&optional effective-clock)
   (interactive)
-  (let ((clock (or effective-clock (cons org-clock-marker
+  (let ((org-clock-into-drawer (org-clock-into-drawer))
+	(clock (or effective-clock (cons org-clock-marker
 					 org-clock-start-time))))
     (unless (marker-buffer (car clock))
       (error "No clock is currently running"))
@@ -1216,16 +1233,17 @@ When FIND-UNCLOSED is non-nil, first check if there is an unclosed clock
 line and position cursor in that line."
   (org-back-to-heading t)
   (catch 'exit
-    (let ((beg (save-excursion
-		 (beginning-of-line 2)
-		 (or (bolp) (newline))
-		 (point)))
-	  (end (progn (outline-next-heading) (point)))
-	  (re (concat "^[ \t]*" org-clock-string))
-	  (cnt 0)
-	  (drawer (if (stringp org-clock-into-drawer)
-		      org-clock-into-drawer "LOGBOOK"))
-	  first last ind-last)
+    (let* ((org-clock-into-drawer (org-clock-into-drawer))
+	   (beg (save-excursion
+		  (beginning-of-line 2)
+		  (or (bolp) (newline))
+		  (point)))
+	   (end (progn (outline-next-heading) (point)))
+	   (re (concat "^[ \t]*" org-clock-string))
+	   (cnt 0)
+	   (drawer (if (stringp org-clock-into-drawer)
+		       org-clock-into-drawer "LOGBOOK"))
+	   first last ind-last)
       (goto-char beg)
       (when (and find-unclosed
 		 (re-search-forward

lisp/org.el

@@ -2375,7 +2375,7 @@ When nil, state changes notes will be inserted after the headline and
 any scheduling and clock lines, but not inside a drawer.
 
 The value of this variable should be the name of the drawer to use.
-LOGBOOK is proposed at the default drawer for this purpose, you can
+LOGBOOK is proposed as the default drawer for this purpose, you can
 also set this to a string to define the drawer of your choice.
 
 A value of t is also allowed, representing \"LOGBOOK\".