Fix cursor display when invisible text is at line beginning

Fix cursor display when invisible text is at line beginning

* src/xdisp.c (redisplay_window): When scrolling fails to show
point, prefer using the desired matrix if possible for finding the
fallback glyph row for displaying the cursor.  (Bug#22098)
(row_containing_pos): Exit the loop as soon as we hit the first
disabled glyph row.  Otherwise we risk accessing garbled data and
departing to the no-no land.