b2/test/sub{break,cont}: code after named and unnamed jump is handled differently

Now we handle both code paths. Should probably unify the diagnostic some
day, too.

b2/test/subbreak

@@ -112,7 +112,22 @@ EOF
 
 #------------------------------------------------------------------------------
 
-tst_fail "substitutions: break inside block " -q <<EOF
+tst_fail "substitutions: unnamed break inside block " -q <<EOF
+!-s
+foo = x
+foo = * {
+	break
+	foo = x
+}
+EOF
+
+expect <<EOF
+s:4: syntax error
+EOF
+
+#------------------------------------------------------------------------------
+
+tst_fail "substitutions: nmbed break inside block " -q <<EOF
 !-s
 foo = x
 foo = * {