VM: Fix memory leaks during isolate spawning

runtime/vm/isolate.h

 // Copyright (c) 2013, 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.
 
 #ifndef RUNTIME_VM_ISOLATE_H_
 #define RUNTIME_VM_ISOLATE_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/atomic.h"
@@ skipping 43 matching lines @@
 class RawGrowableObjectArray;
 class RawMint;
 class RawObject;
 class RawInteger;
 class RawFloat32x4;
 class RawInt32x4;
 class RawUserTag;
 class SafepointHandler;
 class SampleBuffer;
 class SendPort;
+class SerializedObjectBuffer;
 class ServiceIdZone;
 class Simulator;
 class StackResource;
 class StackZone;
 class StoreBuffer;
 class StubCode;
 class ThreadRegistry;
 class UserTag;
 
 
@@ skipping 840 matching lines @@
 };
 
 
 class IsolateSpawnState {
  public:
   IsolateSpawnState(Dart_Port parent_port,
                     Dart_Port origin_id,
                     void* init_data,
                     const char* script_url,
                     const Function& func,
-                    const Instance& message,
+                    SerializedObjectBuffer* message_buffer,
                     Monitor* spawn_count_monitor,
                     intptr_t* spawn_count,
                     const char* package_root,
                     const char* package_config,
                     bool paused,
                     bool errorsAreFatal,
                     Dart_Port onExit,
                     Dart_Port onError);
   IsolateSpawnState(Dart_Port parent_port,
                     void* init_data,
                     const char* script_url,
                     const char* package_root,
                     const char* package_config,
-                    const Instance& args,
-                    const Instance& message,
+                    SerializedObjectBuffer* args_buffer,
+                    SerializedObjectBuffer* message_buffer,
                     Monitor* spawn_count_monitor,
                     intptr_t* spawn_count,
                     bool paused,
                     bool errorsAreFatal,
                     Dart_Port onExit,
                     Dart_Port onError);
   ~IsolateSpawnState();
 
   Isolate* isolate() const { return isolate_; }
   void set_isolate(Isolate* value) { isolate_ = value; }
@@ skipping 44 matching lines @@
   intptr_t* spawn_count_;
 
   Dart_IsolateFlags isolate_flags_;
   bool paused_;
   bool errors_are_fatal_;
 };
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_ISOLATE_H_