Revert change to always call builtins for Array functions....

src/ic.cc

Index: src/ic.cc
===================================================================
--- src/ic.cc	(revision 4073)
+++ src/ic.cc	(working copy)
@@ -458,6 +458,17 @@
   ASSERT(result != Heap::the_hole_value());
 
   if (result->IsJSFunction()) {
+    // Check if there is an optimized (builtin) version of the function.
+    // Ignored this will degrade performance for some Array functions.
+    // Please note we only return the optimized function iff
+    // the JSObject has FastElements.
+    if (object->IsJSObject() && JSObject::cast(*object)->HasFastElements()) {
+      Object* opt = Top::LookupSpecialFunction(JSObject::cast(*object),
+                                               lookup.holder(),
+                                               JSFunction::cast(result));
+      if (opt->IsJSFunction()) return opt;
+    }
+
 #ifdef ENABLE_DEBUGGER_SUPPORT
     // Handle stepping into a function if step into is active.
     if (Debug::StepInActive()) {