[elements] add fast-path for slice with FastSloppyArguments

test/mjsunit/array-slice.js

Index: test/mjsunit/array-slice.js
diff --git a/test/mjsunit/array-slice.js b/test/mjsunit/array-slice.js
index ae0e3bc1ef6fb4793866ce490d951952c0198097..b017dd506a01db61bb38c0c6fe567bbdafe3f043 100644
--- a/test/mjsunit/array-slice.js
+++ b/test/mjsunit/array-slice.js
@@ -228,6 +228,7 @@
   func([]);
   func(['a'], 'a');
   func(['a', 1], 'a', 1);
+  func(['a', 1, 2, 3, 4, 5], 'a', 1, 2, 3, 4, 5);
   func(['a', 1, undefined], 'a', 1, undefined);
   func(['a', 1, undefined, void(0)], 'a', 1, undefined, void(0));
 })();