Reland r24563 and r24564 with fixes cumbersome API leading to leaks.

runtime/lib/object.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/bootstrap_natives.h"
 
 #include "vm/exceptions.h"
+#include "vm/heap.h"
 #include "vm/native_entry.h"
 #include "vm/object.h"
 #include "vm/stack_frame.h"
 #include "vm/symbols.h"
 
 namespace dart {
 
 DECLARE_FLAG(bool, enable_type_checks);
 
 
 DEFINE_NATIVE_ENTRY(Object_cid, 1) {
   const Instance& instance = Instance::CheckedHandle(arguments->NativeArgAt(0));
   return Smi::New(instance.GetClassId());
 }
 
 
+DEFINE_NATIVE_ENTRY(Object_getHash, 1) {
+  const Instance& instance = Instance::CheckedHandle(arguments->NativeArgAt(0));
+  Heap* heap = isolate->heap();
+  return Smi::New(heap->GetHash(instance.raw()));
+}
+
+
+DEFINE_NATIVE_ENTRY(Object_setHash, 2) {
+  const Instance& instance = Instance::CheckedHandle(arguments->NativeArgAt(0));
+  GET_NON_NULL_NATIVE_ARGUMENT(Smi, hash, arguments->NativeArgAt(1));
+  Heap* heap = isolate->heap();
+  heap->SetHash(instance.raw(), hash.Value());
+  return Object::null();
+}
+
+
 DEFINE_NATIVE_ENTRY(Object_toString, 1) {
   const Instance& instance = Instance::CheckedHandle(arguments->NativeArgAt(0));
   const char* c_str = instance.ToCString();
   return String::New(c_str);
 }
 
 
 DEFINE_NATIVE_ENTRY(Object_noSuchMethod, 6) {
   const Instance& instance = Instance::CheckedHandle(arguments->NativeArgAt(0));
   GET_NON_NULL_NATIVE_ARGUMENT(Bool, is_method, arguments->NativeArgAt(1));
@@ skipping 138 matching lines @@
 }
 
 
 DEFINE_NATIVE_ENTRY(AbstractType_toString, 1) {
   const AbstractType& type =
       AbstractType::CheckedHandle(arguments->NativeArgAt(0));
   return type.UserVisibleName();
 }
 
 }  // namespace dart