bug#16681: mouse-autoselect-window missing when switching frames

[martin rudalics <rudalics@gmx.at>]

 > In a system with "focus follows mouse" do the following:
 >
 >     % src/emacs -Q --eval '(setq mouse-autoselect-window t)'
 >     C-x 5 2
 >     <place the two frames side by side>
 >     C-x 2
 >     <go to the second frame>
 >     C-x 2
 >
 > Now move mouse "in circle":
 > - top-left window, then top-right window, then bottom-right window, then
 >    bottom-left window, and if you like it, you can keep doing it for a while.
 > notice how this *should* select each one of the four windows in each cycle,
 > but instead only 2 of those windows are selected: when crossing from one
 > frame to the other the new frame is selected, but that frame's selected
 > window is used as the new selected window instead of using that the
 > window into which the mouse just entered.

Is this still an issue (with ‘focus-follows-mouse’ non-nil, obviously)?

If so, could you please check with GDB whether setting a break point in
the MotionNotify case in xterm.c triggers when the mouse crosses from
one frame into another?  To make such a test practical, please replace
the first line

         x_display_set_last_user_time (dpyinfo, event->xmotion.time);

there by some dummy construct like

	if (any == XFRAME (selected_frame))
	  x_display_set_last_user_time (dpyinfo, event->xmotion.time);
	else
	  x_display_set_last_user_time (dpyinfo, event->xmotion.time);

and put the breakpoint at the last line of that construct.

If it doesn't trigger, we'll probably have to put a similar detection
routine into EnterNotify although such an approach might clash with the
window manager's focus-in handling.

Thanks, martin