patch 8.0.1118: FEAT_WINDOWS adds a lot of #ifdefs

Problem:    FEAT_WINDOWS adds a lot of #ifdefs while it is nearly always
            enabled and only adds 7% to the binary size of the tiny build.
Solution:   Graduate FEAT_WINDOWS.

src/ex_cmds.c

@@ -3225,9 +3225,7 @@ do_write(exarg_T *eap)
 	    if (retval == OK)
 	    {
 		curbuf->b_p_ro = FALSE;
-#ifdef FEAT_WINDOWS
 		redraw_tabline = TRUE;
-#endif
 	    }
 	}
 
@@ -4153,7 +4151,6 @@ do_ecmd(
 #ifdef FEAT_FOLDING
 	/* It's possible that all lines in the buffer changed.  Need to update
 	 * automatic folding for all windows where it's used. */
-# ifdef FEAT_WINDOWS
 	{
 	    win_T	    *win;
 	    tabpage_T	    *tp;
@@ -4162,9 +4159,6 @@ do_ecmd(
 		if (win->w_buffer == curbuf)
 		    foldUpdateAll(win);
 	}
-# else
-	foldUpdateAll(curwin);
-# endif
 #endif
 
 	/* Change directories when the 'acd' option is set. */
@@ -4284,10 +4278,8 @@ do_ecmd(
 	}
     }
 
-#ifdef FEAT_WINDOWS
     /* Check if cursors in other windows on the same buffer are still valid */
     check_lnums(FALSE);
-#endif
 
     /*
      * Did not read the file, need to show some info about the file.
@@ -4583,10 +4575,8 @@ ex_z(exarg_T *eap)
      * 'scroll' */
     if (eap->forceit)
 	bigness = curwin->w_height;
-#ifdef FEAT_WINDOWS
     else if (!ONE_WINDOW)
 	bigness = curwin->w_height - 3;
-#endif
     else
 	bigness = curwin->w_p_scr * 2;
     if (bigness < 1)
@@ -6152,7 +6142,7 @@ free_old_sub(void)
 }
 #endif
 
-#if (defined(FEAT_WINDOWS) && defined(FEAT_QUICKFIX)) || defined(PROTO)
+#if defined(FEAT_QUICKFIX) || defined(PROTO)
 /*
  * Set up for a tagpreview.
  * Return TRUE when it was created.
@@ -6215,9 +6205,7 @@ ex_help(exarg_T *eap)
     FILE	*helpfd;	/* file descriptor of help file */
     int		n;
     int		i;
-#ifdef FEAT_WINDOWS
     win_T	*wp;
-#endif
     int		num_matches;
     char_u	**matches;
     char_u	*p;
@@ -6319,13 +6307,8 @@ ex_help(exarg_T *eap)
      * Re-use an existing help window or open a new one.
      * Always open a new one for ":tab help".
      */
-    if (!bt_help(curwin->w_buffer)
-#ifdef FEAT_WINDOWS
-	    || cmdmod.tab != 0
-#endif
-	    )
+    if (!bt_help(curwin->w_buffer) || cmdmod.tab != 0)
     {
-#ifdef FEAT_WINDOWS
 	if (cmdmod.tab != 0)
 	    wp = NULL;
 	else
@@ -6335,7 +6318,6 @@ ex_help(exarg_T *eap)
 	if (wp != NULL && wp->w_buffer->b_nwindows > 0)
 	    win_enter(wp, TRUE);
 	else
-#endif
 	{
 	    /*
 	     * There is no help window yet.
@@ -6348,7 +6330,6 @@ ex_help(exarg_T *eap)
 	    }
 	    fclose(helpfd);
 
-#ifdef FEAT_WINDOWS
 	    /* Split off help window; put it at far top if no position
 	     * specified, the current window is vertically split and
 	     * narrow. */
@@ -6358,16 +6339,9 @@ ex_help(exarg_T *eap)
 		n |= WSP_TOP;
 	    if (win_split(0, n) == FAIL)
 		goto erret;
-#else
-	    /* use current window */
-	    if (!can_abandon(curbuf, FALSE))
-		goto erret;
-#endif
 
-#ifdef FEAT_WINDOWS
 	    if (curwin->w_height < p_hh)
 		win_setheight((int)p_hh);
-#endif
 
 	    /*
 	     * Open help file (do_ecmd() will set b_help flag, readfile() will
@@ -6377,12 +6351,7 @@ ex_help(exarg_T *eap)
 	    alt_fnum = curbuf->b_fnum;
 	    (void)do_ecmd(0, NULL, NULL, NULL, ECMD_LASTL,
 			  ECMD_HIDE + ECMD_SET_HELP,
-#ifdef FEAT_WINDOWS
-			  NULL  /* buffer is still open, don't store info */
-#else
-			  curwin
-#endif
-		    );
+			  NULL);  /* buffer is still open, don't store info */
 	    if (!cmdmod.keepalt)
 		curwin->w_alt_fnum = alt_fnum;
 	    empty_fnum = curbuf->b_fnum;
@@ -6425,7 +6394,6 @@ erret:
     void
 ex_helpclose(exarg_T *eap UNUSED)
 {
-#if defined(FEAT_WINDOWS)
     win_T *win;
 
     FOR_ALL_WINDOWS(win)
@@ -6436,7 +6404,6 @@ ex_helpclose(exarg_T *eap UNUSED)
 	    return;
 	}
     }
-#endif
 }
 
 #if defined(FEAT_MULTI_LANG) || defined(PROTO)
@@ -8350,9 +8317,7 @@ ex_drop(exarg_T *eap)
     int		split = FALSE;
     win_T	*wp;
     buf_T	*buf;
-# ifdef FEAT_WINDOWS
     tabpage_T	*tp;
-# endif
 
     /*
      * Check if the first argument is already being edited in a window.  If
@@ -8372,7 +8337,6 @@ ex_drop(exarg_T *eap)
     if (ARGCOUNT == 0)
 	return;
 
-# ifdef FEAT_WINDOWS
     if (cmdmod.tab)
     {
 	/* ":tab drop file ...": open a tab for each argument that isn't
@@ -8381,7 +8345,6 @@ ex_drop(exarg_T *eap)
 	ex_all(eap);
     }
     else
-# endif
     {
 	/* ":drop file ...": Edit the first argument.  Jump to an existing
 	 * window if possible, edit in current window if the current buffer
@@ -8392,9 +8355,7 @@ ex_drop(exarg_T *eap)
 	{
 	    if (wp->w_buffer == buf)
 	    {
-# ifdef FEAT_WINDOWS
 		goto_tabpage_win(tp, wp);
-# endif
 		curwin->w_arg_idx = 0;
 		return;
 	    }
@@ -8408,16 +8369,9 @@ ex_drop(exarg_T *eap)
 	 */
 	if (!buf_hide(curbuf))
 	{
-# ifdef FEAT_WINDOWS
 	    ++emsg_off;
-# endif
 	    split = check_changed(curbuf, CCGD_AW | CCGD_EXCMD);
-# ifdef FEAT_WINDOWS
 	    --emsg_off;
-# else
-	    if (split)
-		return;
-# endif
 	}
 
 	/* Fake a ":sfirst" or ":first" command edit the first argument. */