Arrays created with new Array(n) are not assumed to be sparse unless the give...

src/builtins.cc

Index: src/builtins.cc
===================================================================
--- src/builtins.cc	(revision 1416)
+++ src/builtins.cc	(working copy)
@@ -155,7 +155,7 @@
     Object* obj = BUILTIN_ARG(1);
     if (obj->IsSmi()) {
       int len = Smi::cast(obj)->value();
-      if (len >= 0 && len < JSObject::kMaxFastElementsLength) {
+      if (len >= 0 && len < JSObject::kInitialMaxFastElementArray) {
         Object* obj = Heap::AllocateFixedArrayWithHoles(len);
         if (obj->IsFailure()) return obj;
         array->SetContent(FixedArray::cast(obj));