Fix bug #7939 with bidi display of hscrolled lines.
xdisp.c <this_line_min_pos>: New variable. (move_it_in_display_line_to): Record in this_line_min_pos the smallest position iterated across. (display_line): Use this_line_min_pos to record the smallest position in the line even if that position is not displayed due to hscrolling.
Showing with 40 additions and 7 deletions