* window.h (struct window): Convert window_end_pos and

* window.h (struct window): Convert window_end_pos and
window_end_vpos from Lisp_Object to ptrdiff_t and int, respectively.
(wset_window_end_pos, wset_window_end_vpos): Remove.
* dispnew.c (adjust_glyph_matrix):
* window.c (Fwindow_end, replace_window, set_window_buffer)
(make_window):
* xdisp.c (check_window_end, move_it_to, redisplay_internal)
(set_vertical_scroll_bar, redisplay_window, try_window)
(try_window_reusing_current_matrix, find_first_unchanged_at_end_row)
(try_window_id, decode_mode_spec, mouse_face_from_buffer_pos)
(note_mouse_highlight): Adjust users.
(try_cursor_movement): Likewise.  Convert old precondition to eassert.
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