Fix bug in mjsunit/const-eval-init causing objects to be initialized to undef...

test/mjsunit/const-eval-init.js

Index: test/mjsunit/const-eval-init.js
===================================================================
--- test/mjsunit/const-eval-init.js	(revision 4816)
+++ test/mjsunit/const-eval-init.js	(working copy)
@@ -91,7 +91,7 @@
   var source = "";
   // Introduce 100 properties on the context extension object to force
   // it in slow case.
-  for (var i = 0; i < 100; i++) source += ("var a" + i + " = i;");
+  for (var i = 0; i < 100; i++) source += ("var a" + i + " = " + i + ";");
   source += "const x = 10; assertEquals(10, x); x = 11; assertEquals(10, x)";
   eval(source);
 }