New internal-border face and args for select-window and x-focus-frame

Add `internal-border' face and handle it whenever clearing the
internal border.  If NORECORD equals the symbol
'mark-for-redisplay', `select-window' will not record the window
but still mark it for redisplay.  The new argument NOACTIVATE
for `x-focus-frame' tries to not activate FRAME when set.

* lisp/faces.el (internal-border): New face.
* lisp/mwheel.el (mwheel-scroll): Select window to scroll with
`mark-for-redisplay'.
* lisp/scroll-bar.el (scroll-bar-drag)
(scroll-bar-horizontal-drag, scroll-bar-scroll-down)
(scroll-bar-scroll-up, scroll-bar-toolkit-scroll)
(scroll-bar-toolkit-horizontal-scroll): Select window to scroll
with `mark-for-redisplay'.
* lisp/window.el (handle-select-window): When
`focus-follows-mouse' is not 'auto-raise' try to not activate
FRAME.
* src/dispextern.h (face_id): Add INTERNAL_BORDER_FACE_ID.
* src/frame.c (Fx_focus_frame): New argument NOACTIVATE.
* src/frame.h (x_focus_frame): Update extern declaration.
* src/gtkutil.c (xg_clear_under_internal_border): Remove
function.
(xg_frame_resized, xg_frame_set_char_size): Call
x_clear_under_internal_border.
(xg_tool_bar_callback): Adapt x_focus_frame call.
* src/gtkutil.h (xg_clear_under_internal_border): Remove
declaration.
* src/nsfns.m (x_focus_frame): Add argument NOACTIVATE.
* src/w32fns.c (x_clear_under_internal_border): Fill border
with internal-border background if specified.
* src/w32term.h (x_clear_under_internal_border): Add extern
declaration.
* src/w32term.c (x_after_update_window_line): Fill border
with internal-border background if specified.
(w32_set_vertical_scroll_bar, w32_set_horizontal_scroll_bar)
(x_scroll_bar_clear, w32_read_socket): Call
x_clear_under_internal_border.
(x_focus_frame): New argument NOACTIVATE.
* src/window.c (select_window): Mark WINDOW for redisplay when
NORECORD equals 'mark-for-redisplay'.
(Fselect_window): Update doc-string.
(syms_of_window): Define Qmark_for_redisplay.
* src/xdisp.c (clear_garbaged_frames, echo_area_display)
(redisplay_internal): Call x_clear_under_internal_border.
* src/xfaces.c (lookup_basic_face): Handle `window-divider'
and `internal-border' faces.
(realize_basic_faces): Realize `internal-border' face.
(syms_of_xfaces): Define Qinternal_border.
* src/xfns.c (x_set_internal_border_width): Remove call for
xg_clear_under_internal_border.
(x_focus_frame): New argument NOACTIVATE.  When non-nil try to not
activate frame.
* src/xterm.c (x_fill_rectangle): No more static.
(x_clear_under_internal_border, x_after_update_window_line):
Fill border with internal-border background if specified.
(xt_horizontal_action_hook): Rewrite.
(handle_one_xevent): Call x_clear_under_internal_border.
* src/xterm.h (x_fill_rectangle): Add extern declaration.

lisp/mwheel.el

@@ -220,6 +220,9 @@ non-Windows systems."
          (mods
 	  (delq 'click (delq 'double (delq 'triple (event-modifiers event)))))
          (amt (assoc mods mouse-wheel-scroll-amount)))
+    (unless (eq scroll-window selected-window)
+      ;; Mark window to be scrolled for redisplay.
+      (select-window scroll-window 'mark-for-redisplay))
     ;; Extract the actual amount or find the element that has no modifiers.
     (if amt (setq amt (cdr amt))
       (let ((list-elt mouse-wheel-scroll-amount))