Remove some remaining references to XEmacs

* lisp/allout.el (allout-overlay-preparations):
* lisp/cedet/semantic/decorate/include.el
(semantic-decoration-unknown-include-menu)
(semantic-decoration-fileless-include-menu):
* lisp/cedet/semantic/idle.el (semantic-idle-scheduler-setup-timers):
* lisp/vc/ediff-init.el:
* lisp/vc/ediff-util.el (ediff-mode): Remove some remaining references
to XEmacs.

lisp/allout.el

@@ -1601,7 +1601,7 @@ So `allout-post-command-business' should not reactivate it...")
   ;; the _transient_ opening of invisible text during isearch -- is keyed to
   ;; presence of the isearch-open-invisible property -- even though this
   ;; property controls the isearch _arrival_ behavior.  This is the case at
-  ;; least in emacs 21, 22.1, and xemacs 21.4.
+  ;; least in emacs 21, 22.1.
   (put 'allout-exposure-category 'isearch-open-invisible
        #'allout-isearch-end-handler)
   (put 'allout-exposure-category 'insert-in-front-hooks

lisp/cedet/semantic/decorate/include.el

@@ -514,9 +514,7 @@ See the Semantic manual node on SemanticDB for more about search paths.")
 Argument EVENT describes the event that caused this function to be called."
   (interactive "e")
   (let* ((startwin (selected-window))
-	 ;; This line has an issue in XEmacs.
-	 (win (semantic-event-window event))
-	 )
+         (win (semantic-event-window event)))
     (select-window win t)
     (save-excursion
       ;(goto-char (window-start win))
@@ -557,9 +555,7 @@ searches, but you cannot visit this include.\n\n")
 Argument EVENT describes the event that caused this function to be called."
   (interactive "e")
   (let* ((startwin (selected-window))
-	 ;; This line has an issue in XEmacs.
-	 (win (semantic-event-window event))
-	 )
+         (win (semantic-event-window event)))
     (select-window win t)
     (save-excursion
       ;(goto-char (window-start win))

lisp/cedet/semantic/idle.el

@@ -102,7 +102,6 @@ it is unlikely the user would be ready to type again right away."
 
 (defun semantic-idle-scheduler-setup-timers ()
   "Lazy initialization of the auto parse idle timer."
-  ;; REFRESH THIS FUNCTION for XEMACS FOIBLES
   (or (timerp semantic-idle-scheduler-timer)
       (setq semantic-idle-scheduler-timer
             (run-with-idle-timer

lisp/vc/ediff-init.el

@@ -49,7 +49,6 @@ that Ediff doesn't know about.")
   (declare (obsolete nil "27.1"))
   window-system)
 
-;; in XEmacs: device-type is tty on tty and stream in batch.
 (defun ediff-window-display-p ()
   (and window-system
        (not (memq window-system '(tty pc stream)))))

lisp/vc/ediff-util.el

@@ -87,12 +87,10 @@ Commands:
   (kill-all-local-variables)
   (setq major-mode 'ediff-mode)
   (setq mode-name "Ediff")
-  ;; We use run-hooks instead of run-mode-hooks for two reasons.
+  ;; We use run-hooks instead of run-mode-hooks for one reason.
   ;; The ediff control buffer is read-only and it is not supposed to be
   ;; modified by minor modes and such. So, run-mode-hooks doesn't do anything
   ;; useful here on top of what run-hooks does.
-  ;; Second, changing run-hooks to run-mode-hooks would require an
-  ;; if-statement, since XEmacs doesn't have this.
   (run-hooks 'ediff-mode-hook))
 
 
@@ -3938,8 +3936,8 @@ If Emacs happens to dump core, this is NOT an Ediff problem---it is
 an Emacs bug.  Report this to Emacs maintainers.
 
 Another popular topic for reports is compilation messages.  Because Ediff
-interfaces to several other packages and runs under Emacs and XEmacs,
-byte-compilation may produce output like this:
+interfaces to several other packages, byte-compilation may produce output
+like this:
 
        While compiling toplevel forms in file ediff.el:
 	 ** reference to free variable zzz