Fix name shown by devtools for subclasses.

test/cctest/test-heap-profiler.cc

 // Copyright 2011 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 1800 matching lines @@
 TEST(GetConstructorName) {
   LocalContext env;
   v8::HandleScope scope(env->GetIsolate());
 
   CompileRun(
       "function Constructor1() {};\n"
       "var obj1 = new Constructor1();\n"
       "var Constructor2 = function() {};\n"
       "var obj2 = new Constructor2();\n"
       "var obj3 = {};\n"
-      "obj3.constructor = function Constructor3() {};\n"
+      "obj3.__proto__ = { constructor: function Constructor3() {} };\n"
       "var obj4 = {};\n"
       "// Slow properties\n"
       "for (var i=0; i<2000; ++i) obj4[\"p\" + i] = i;\n"
-      "obj4.constructor = function Constructor4() {};\n"
+      "obj4.__proto__ = { constructor: function Constructor4() {} };\n"
       "var obj5 = {};\n"
       "var obj6 = {};\n"
       "obj6.constructor = 6;");
   v8::Local<v8::Object> js_global =
       env->Global()->GetPrototype().As<v8::Object>();
   v8::Local<v8::Object> obj1 = js_global->Get(v8_str("obj1")).As<v8::Object>();
   i::Handle<i::JSObject> js_obj1 =
       i::Handle<i::JSObject>::cast(v8::Utils::OpenHandle(*obj1));
   CHECK_EQ(0, StringCmp(
       "Constructor1", i::V8HeapExplorer::GetConstructorName(*js_obj1)));
   v8::Local<v8::Object> obj2 = js_global->Get(v8_str("obj2")).As<v8::Object>();
   i::Handle<i::JSObject> js_obj2 =
       i::Handle<i::JSObject>::cast(v8::Utils::OpenHandle(*obj2));
   CHECK_EQ(0, StringCmp(
       "Constructor2", i::V8HeapExplorer::GetConstructorName(*js_obj2)));
   v8::Local<v8::Object> obj3 = js_global->Get(v8_str("obj3")).As<v8::Object>();
   i::Handle<i::JSObject> js_obj3 =
       i::Handle<i::JSObject>::cast(v8::Utils::OpenHandle(*obj3));
-  // TODO(verwaest): Restore to Constructor3 once supported by the
-  // heap-snapshot-generator.
-  CHECK_EQ(
-      0, StringCmp("Object", i::V8HeapExplorer::GetConstructorName(*js_obj3)));
+  CHECK_EQ(0, StringCmp("Constructor3",
+                        i::V8HeapExplorer::GetConstructorName(*js_obj3)));
   v8::Local<v8::Object> obj4 = js_global->Get(v8_str("obj4")).As<v8::Object>();
   i::Handle<i::JSObject> js_obj4 =
       i::Handle<i::JSObject>::cast(v8::Utils::OpenHandle(*obj4));
-  // TODO(verwaest): Restore to Constructor4 once supported by the
-  // heap-snapshot-generator.
-  CHECK_EQ(
-      0, StringCmp("Object", i::V8HeapExplorer::GetConstructorName(*js_obj4)));
+  CHECK_EQ(0, StringCmp("Constructor4",
+                        i::V8HeapExplorer::GetConstructorName(*js_obj4)));
   v8::Local<v8::Object> obj5 = js_global->Get(v8_str("obj5")).As<v8::Object>();
   i::Handle<i::JSObject> js_obj5 =
       i::Handle<i::JSObject>::cast(v8::Utils::OpenHandle(*obj5));
   CHECK_EQ(0, StringCmp(
       "Object", i::V8HeapExplorer::GetConstructorName(*js_obj5)));
   v8::Local<v8::Object> obj6 = js_global->Get(v8_str("obj6")).As<v8::Object>();
   i::Handle<i::JSObject> js_obj6 =
       i::Handle<i::JSObject>::cast(v8::Utils::OpenHandle(*obj6));
   CHECK_EQ(0, StringCmp(
       "Object", i::V8HeapExplorer::GetConstructorName(*js_obj6)));
@@ skipping 937 matching lines @@
   map.AddRange(ToAddress(0x180), 0x80, 6U);
   map.AddRange(ToAddress(0x180), 0x80, 7U);
   CHECK_EQ(7u, map.GetTraceNodeId(ToAddress(0x180)));
   CHECK_EQ(5u, map.GetTraceNodeId(ToAddress(0x200)));
   CHECK_EQ(3u, map.size());
 
   map.Clear();
   CHECK_EQ(0u, map.size());
   CHECK_EQ(0u, map.GetTraceNodeId(ToAddress(0x400)));
 }