(IT_set_face): Don't swap face colors when highlight or

(IT_set_face): Don't swap face colors when highlight or
fp->tty_reverse_p is set, unless the computed colors are identical
to frame colors.  Print both original and computed colors to
termscript file.
(IT_write_glyphs): Track the changes in handling of composite
characters.
(IT_set_frame_parameters): Don't set frame colors from
unspecified-fg and unspecified-bg pseudo-colors.