Support ':relative-width' space display spec on text-mode terminals

* src/xdisp.c (produce_stretch_glyph): Support ':relative-width'
space display spec on text-mode terminals, by calling
PRODUCE_GLYPHS instead of x_produce_glyphs.  Remove the HAVE_WINDOW_SYSTEM
guards from the supporting code, as well as the test for a GUI frame.

1 files changed, 3 insertions, 2 deletions

diff --git a/doc/lispref/display.texi b/doc/lispref/display.texi
index 6a30adf9c90..452462adcfc 100644
--- a/doc/lispref/display.texi
+++ b/doc/lispref/display.texi
@@ -4387,8 +4387,9 @@ width.  @var{width} can also be a @dfn{pixel width} specification
 Specifies that the width of the stretch should be computed from the
 first character in the group of consecutive characters that have the
 same @code{display} property.  The space width is the pixel width of
-that character, multiplied by @var{factor}.  This specification is
-only supported on graphic terminals.
+that character, multiplied by @var{factor}.  (On text-mode terminals,
+the ``pixel width'' of a character is usually 1, but it could be more
+for TABs and double-width CJK characters.)
 
 @item :align-to @var{hpos}
 Specifies that the space should be wide enough to reach @var{hpos}.