Fix some usage of "this" in builtins

src/ia32/codegen-ia32.cc

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 5165 matching lines @@
   destination()->false_target()->Branch(zero);
   Result temp = allocator()->Allocate();
   ASSERT(temp.is_valid());
   __ CmpObjectType(obj.reg(), JS_FUNCTION_TYPE, temp.reg());
   obj.Unuse();
   temp.Unuse();
   destination()->Split(equal);
 }
 
 
+void CodeGenerator::GenerateIsUndetectableObject(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 1);
+  Load(args->at(0));
+  Result obj = frame_->Pop();
+  obj.ToRegister();
+  __ test(obj.reg(), Immediate(kSmiTagMask));
+  destination()->false_target()->Branch(zero);
+  Result temp = allocator()->Allocate();
+  ASSERT(temp.is_valid());
+  __ mov(temp.reg(),
+         FieldOperand(obj.reg(), HeapObject::kMapOffset));
+  __ movzx_b(temp.reg(),
+             FieldOperand(temp.reg(), Map::kBitFieldOffset));
+  __ test(temp.reg(), Immediate(1 << Map::kIsUndetectable));
+  obj.Unuse();
+  temp.Unuse();
+  destination()->Split(not_zero);
+}
+
+
 void CodeGenerator::GenerateIsConstructCall(ZoneList<Expression*>* args) {
   ASSERT(args->length() == 0);
 
   // Get the frame pointer for the calling frame.
   Result fp = allocator()->Allocate();
   __ mov(fp.reg(), Operand(ebp, StandardFrameConstants::kCallerFPOffset));
 
   // Skip the arguments adaptor frame if it exists.
   Label check_frame_marker;
   __ cmp(Operand(fp.reg(), StandardFrameConstants::kContextOffset),
@@ skipping 4593 matching lines @@
 
   // Call the runtime; it returns -1 (less), 0 (equal), or 1 (greater)
   // tagged as a small integer.
   __ bind(&runtime);
   __ TailCallRuntime(ExternalReference(Runtime::kStringCompare), 2, 1);
 }
 
 #undef __
 
 } }  // namespace v8::internal