bug fix for display property of the form ((height 0.5))

[Kenichi Handa <handa@m17n.org>]

I've just installed the attached fix for the trunk to fix
the problem of something like this doesn't work.

(insert (propertize "abc" 'display '((height 0.5))))

Should I install it for the branch too?

---
Kenichi Handa
handa@m17n.org

2009-07-27  Kenichi Handa  <handa@m17n.org>

	* xfaces.c (face_with_height): Call font_clear_prop.

Index: xfaces.c
===================================================================
RCS file: /cvsroot/emacs/emacs/src/xfaces.c,v
retrieving revision 1.437
retrieving revision 1.438
diff -u -r1.437 -r1.438
--- xfaces.c	29 Jun 2009 05:28:56 -0000	1.437
+++ xfaces.c	27 Jul 2009 04:19:03 -0000	1.438
@@ -4958,6 +4958,7 @@
   face = FACE_FROM_ID (f, face_id);
   bcopy (face->lface, attrs, sizeof attrs);
   attrs[LFACE_HEIGHT_INDEX] = make_number (height);
+  font_clear_prop (attrs, FONT_SIZE_INDEX);
   face_id = lookup_face (f, attrs);
 #endif /* HAVE_WINDOW_SYSTEM */