Fix display of R2L continued lines in partial-width windows on a TTY.

 xdisp.c: (extend_face_to_end_of_line): In almost-filled rows, extend only
 if the row is R2L and not continued.

src/ChangeLog

@@ -2,6 +2,8 @@
 	* xdisp.c (find_row_end): New function, refactored from display_line.
 	(display_line): Use it.
+	(extend_face_to_end_of_line): In almost-filled rows, extend only
+	if the row is R2L and not continued.
 2010-04-27  Eli Zaretskii  <eliz@gnu.org>

src/xdisp.c

@@ -16948,8 +16948,13 @@ extend_face_to_end_of_line (it)
   /* If line is already filled, do nothing.  Non window-system frames
      get a grace of one more ``pixel'' because their characters are
-     1-``pixel'' wide, so they hit the equality too early.  */
-  if (it->current_x >= it->last_visible_x + !FRAME_WINDOW_P (f))
+     1-``pixel'' wide, so they hit the equality too early.  This grace
+     is needed only for R2L rows that are not continued, to produce
+     one extra blank where we could display the cursor.  */
+  if (it->current_x >= it->last_visible_x
+      + (!FRAME_WINDOW_P (f)
+	 && it->glyph_row->reversed_p
+	 && !it->glyph_row->continued_p))
     return;
   /* Face extension extends the background and box of IT->face_id