Final preparations for new window resize code.

Final preparations for new window resize code.

* window.c (replace_window): Rename second argument REPLACEMENT to
NEW.  New third argument SETFLAG.  Rewrite.
(delete_window, make_dummy_parent): Call replace_window with
third argument 1.
(window_list_1): Move down in code.
(run_window_configuration_change_hook): Move set_buffer part
before select_frame_norecord part in order to unwind correctly.
Rename count1 to count.
(recombine_windows, delete_deletable_window, resize_root_window)
(Fdelete_other_windows_internal)
(Frun_window_configuration_change_hook, make_parent_window)
(resize_window_check, resize_window_apply, Fresize_window_apply)
(resize_frame_windows, Fsplit_window_internal)
(Fdelete_window_internal, Fresize_mini_window_internal): New
functions.
(syms_of_window): New variables Vwindow_splits and Vwindow_nest.