Fix background color beyond EOB and cursor display

Fix background color beyond EOB and cursor display

* src/xdisp.c: 	(maybe_produce_line_number): Use the default face
for background of the blank glyphs in the line-number area which
are drawn beyond EOB.
(display_line): Reset the glyph row's displays_text_p flag only on
empty lines that don't display line numbers.  This fixes cursor
display beyond EOB.  Fix the bidi information in the glyphs
produced for line numbers.  Set the avoid_cursor_p flag of glyphs
produced for line numbers.