(fix_glyph): New function.

(fix_glyph): New function.
(display_text_line, display_string): Use fix_glyph.

(copy_rope): Function deleted.
(copy_part_of_rope): Merge the glyph's face using compute_glyph_face.
Take frame as additional arg.
(display_text_line): Use copy_part_of_rope always, not copy_rope.
Pass the frame as arg.
(display_string): Likewise.

(display_count_lines): Pass new arg to scan_buffer.

(display_menu_bar): Pass explicit max arg to display_string.
(display_string): New arg OBEY_WINDOW_WIDTH.  All callers changed.