Fix --shift and --match-shift on command line with fractional parameter.

Setting --shift calls calc_shift_count() and setting --match-shift calls
calc_match_shift(). When the parameter begins with a '.', these calculate
the value as a fraction of the screen width. But at startup when these
functions are called from scan_option(), the screen width is not yet known.
So call them in get_term() after the screen width is first determined.
Previously this was done for calc_jump_sline() but it also needs to be
done for the other two.

NEWS

@@ -23,6 +23,9 @@
 
 * Fix bug when using #stop in a lesskey file (github #551).
 
+* Fix bug when using --shift or --match-shift on command line with
+  a parameter starting with '.' (github #553).
+
 ======================================================================
 
 	Major changes between "less" versions 643 and 661

screen.c

@@ -911,7 +911,17 @@ static void scrsize(void)
 	}
 	if (sc_width <= 0)
 		sc_width = DEF_SC_WIDTH;
+	screen_size_changed();
+}
+
+/*
+ * Recalculate things that depend on the screen size.
+ */
+public void screen_size_changed(void)
+{
 	calc_jump_sline();
+	calc_shift_count();
+	calc_match_shift();
 }
 
 #if MSDOS_COMPILER==MSOFTC

signal.c

@@ -248,9 +248,7 @@ public void psignals(void)
 		if (sc_width != old_width || sc_height != old_height)
 		{
 			wscroll = (sc_height + 1) / 2;
-			calc_jump_sline();
-			calc_shift_count();
-			calc_match_shift();
+			screen_size_changed();
 		}
 		screen_trashed();
 	}

version.c

@@ -1023,7 +1023,8 @@ v659  6/20/24   Fix typo in help.
 v660  6/24/24   Fix bug in ixerror.
 v661  6/29/24   Simpler fix for ixerror bug.
 v662            Fix build with --with-secure; improve true colors on Windows;
-                fix crash with --header; fix crash with -S.
+                fix crash with --header; fix crash with -S; fix #stop;
+				fix --shift with fractional parameter.
 */
 
 char version[] = "662x";