Stop keeping multiple doc copies for items defined multiple times

It was always a nuisance to keep all the copies in sync.
* src/doc.c (Fsnarf_documentation): Don't skip entire files.
Instead, skip individual doc strings starting with "SKIP".
* doc/lispref/internals.texi (Writing Emacs Primitives):
Mention this skipping.
* lisp/term/ns-win.el, lisp/term/pc-win.el, src/dosfns.c:
* src/frame.c, src/nsfns.m, src/nsmenu.m, src/nsterm.m:
* src/w16select.c, src/w32fns.c, src/w32menu.c, src/w32select.c:
* src/w32term.c, src/xmenu.c: Remove duplicated doc strings.
* src/xfns.c: Merge in information from doc string duplicates.

1 files changed, 4 insertions, 23 deletions

diff --git a/src/w32term.c b/src/w32term.c
index c1d039c1375..97afb678c1d 100644
--- a/src/w32term.c
+++ b/src/w32term.c
@@ -7329,14 +7329,7 @@ syms_of_w32term (void)
   DEFSYM (Qrenamed_to, "renamed-to");
 
   DEFVAR_LISP ("x-wait-for-event-timeout", Vx_wait_for_event_timeout,
-    doc: /* How long to wait for X events.
-
-Emacs will wait up to this many seconds to receive X events after
-making changes which affect the state of the graphical interface.
-Under some window managers this can take an indefinite amount of time,
-so it is important to limit the wait.
-
-If set to a non-float value, there will be no wait at all.  */);
+    doc: /* SKIP: real doc in xterm.c.  */);
   Vx_wait_for_event_timeout = make_float (0.1);
 
   DEFVAR_INT ("w32-num-mouse-buttons",
@@ -7390,28 +7383,16 @@ the cursor have no effect.  */);
      from cus-start.el and other places, like "M-x set-variable".  */
   DEFVAR_BOOL ("x-use-underline-position-properties",
                x_use_underline_position_properties,
-     doc: /* Non-nil means make use of UNDERLINE_POSITION font properties.
-A value of nil means ignore them.  If you encounter fonts with bogus
-UNDERLINE_POSITION font properties, for example 7x13 on XFree prior
-to 4.1, set this to nil.  You can also use `underline-minimum-offset'
-to override the font's UNDERLINE_POSITION for small font display
-sizes.  */);
+     doc: /* SKIP: real doc in xterm.c.  */);
   x_use_underline_position_properties = 0;
 
   DEFVAR_BOOL ("x-underline-at-descent-line",
                x_underline_at_descent_line,
-     doc: /* Non-nil means to draw the underline at the same place as the descent line.
-A value of nil means to draw the underline according to the value of the
-variable `x-use-underline-position-properties', which is usually at the
-baseline level.  The default value is nil.  */);
+     doc: /* SKIP: real doc in xterm.c.  */);
   x_underline_at_descent_line = 0;
 
   DEFVAR_LISP ("x-toolkit-scroll-bars", Vx_toolkit_scroll_bars,
-               doc: /* Which toolkit scroll bars Emacs uses, if any.
-A value of nil means Emacs doesn't use toolkit scroll bars.
-With the X Window system, the value is a symbol describing the
-X toolkit.  Possible values are: gtk, motif, xaw, or xaw3d.
-With MS Windows or Nextstep, the value is t.  */);
+               doc: /* SKIP: real doc in xterm.c.  */);
   Vx_toolkit_scroll_bars = Qt;
 
   DEFVAR_BOOL ("w32-unicode-filenames",