Fix error in sin-cos.js test introduced in r7129.

test/mjsunit/sin-cos.js

Index: test/mjsunit/sin-cos.js
===================================================================
--- test/mjsunit/sin-cos.js	(revision 7131)
+++ test/mjsunit/sin-cos.js	(working copy)
@@ -33,7 +33,7 @@
 }
 
 function cosTest() {
-  assertEquals(0, Math.cos(1));
+  assertEquals(1, Math.cos(0));
   assertEquals(-1, Math.cos(Math.PI));
 }