Fix stub-invoked setter callback handling.

test/cctest/test-api.cc

 // Copyright 2012 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 21609 matching lines @@
   }
   for (int i = 0; i < runs; i++) {
     Local<String> expected;
     if (i != 0) {
       CHECK_EQ(v8_str("escape value"), values[i]);
     } else {
       CHECK(values[i].IsEmpty());
     }
   }
 }
+
+
+static void SetterWhichExpectsThisAndHolderToDiffer(
+    Local<String>, Local<Value>, const v8::PropertyCallbackInfo<void>& info) {
+  CHECK(info.Holder() != info.This());
+}
+
+
+TEST(Regress239669) {

[dcarney, 2014/01/16 07:44:13]

this test doesn't test the stub you changed
please change it to the following

    LocalContext context;
  v8::Isolate* isolate = context->GetIsolate();
  v8::HandleScope scope(isolate);
  Local<ObjectTemplate> templ = ObjectTemplate::New(isolate);
  templ->SetAccessor(v8_str("x"), 0, SetterWhichExpectsThisAndHolderToDiffer);
  context->Global()->Set(v8_str("P"), templ->NewInstance());

  CompileRun(
     "function C1() {"
      "  this.x = 23;"
      "};"
      "C1.prototype = P;"
      "for (var i = 0; i < 4; i++ ) {"
      "  new C1();"
      "}");

[sof, 2014/01/16 08:00:16]

Thanks, will do.

(But what's there exercises that code path for me (x64, bleeding_edge.) )

[sof, 2014/01/16 08:44:11]

Done.

+  // Regress618 triggers the StoreCallbackProperty() code path
+  // we're after; this is a reduced version of it.
+  const char* source = "function C1() {"
+                       "  this.x = 23;"
+                       "};"
+                       "C1.prototype = P;";
+
+  LocalContext context;
+  v8::Isolate* isolate = context->GetIsolate();
+  v8::HandleScope scope(isolate);
+
+  // Use a simple object as prototype.
+  v8::Local<v8::Object> prototype = v8::Object::New(isolate);
+  prototype->Set(v8_str("y"), v8_num(42));
+  context->Global()->Set(v8_str("P"), prototype);
+
+  CompileRun(source);
+  v8::Local<v8::Script> script = v8::Script::Compile(v8_str("new C1();"));
+  for (int i = 0; i < 2; i++) {
+    v8::Handle<v8::Object>::Cast(script->Run());
+  }
+
+  Local<ObjectTemplate> templ = ObjectTemplate::New(isolate);
+  templ->SetAccessor(v8_str("x"), 0, SetterWhichExpectsThisAndHolderToDiffer);
+  context->Global()->Set(v8_str("P"), templ->NewInstance());
+
+  CompileRun(source);
+  script = v8::Script::Compile(v8_str("new C1();"));
+  for (int i = 0; i < 2; i++) {
+    v8::Handle<v8::Object>::Cast(script->Run());
+  }
+}