ash: fix `trap`

function                                             old     new   delta
forkshell                                            738     810     +72
popstring                                            134     140      +6
parse_command                                       1460    1463      +3
evalvar                                             1373    1371      -2
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/1 up/down: 81/-2)              Total: 79 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/shell/ash_test/ash-signals/savetrap.tests b/shell/ash_test/ash-signals/savetrap.tests
new file mode 100755
index 0000000..6492e86
--- /dev/null
+++ b/shell/ash_test/ash-signals/savetrap.tests
@@ -0,0 +1,6 @@
+trap 'echo WINCH!' SIGWINCH
+v=` trap   `
+echo $v
+v=`trap`
+echo $v
+echo Done