Ensure class prototype objects have the right Map::constructor field

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 24612 matching lines @@
 
   v8::Handle<v8::Value> result = CompileRun("%_GetPrototype(object)");
   CHECK(result->Equals(proto2));
 
   result = CompileRun(
       "function f() { return %_GetPrototype(object); }"
       "%OptimizeFunctionOnNextCall(f);"
       "f()");
   CHECK(result->Equals(proto2));
 }
+
+
+TEST(ClassPrototypeCreationContext) {
+  i::FLAG_harmony_classes = true;
+  v8::Isolate* isolate = CcTest::isolate();
+  v8::HandleScope handle_scope(isolate);
+  LocalContext env;
+
+  Handle<Object> result = Handle<Object>::Cast(
+      CompileRun("'use strict'; class Example { }; Example.prototype"));
+  CHECK(env.local() == result->CreationContext());
+}