Add support for big integers to the native message format

runtime/vm/snapshot.h

 // Copyright (c) 2012, 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 VM_SNAPSHOT_H_
 #define VM_SNAPSHOT_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/bitfield.h"
@@ skipping 467 matching lines @@
   // Writes a message of integers.
   void WriteMessage(intptr_t field_count, intptr_t *data);
 
   void WriteCMessage(Dart_CObject* object);
 
   void FinalizeBuffer() {
     BaseWriter::FinalizeBuffer(Snapshot::kMessage);
   }
 
  private:
-  static const intptr_t kDartCObjectTypeBits = 3;
+  static const intptr_t kDartCObjectTypeBits = 4;
   static const intptr_t kDartCObjectTypeMask = (1 << kDartCObjectTypeBits) - 1;
   static const intptr_t kDartCObjectMarkMask = ~kDartCObjectTypeMask;
   static const intptr_t kDartCObjectMarkOffset = 1;
 
   void MarkCObject(Dart_CObject* object, intptr_t object_id);
   void UnmarkCObject(Dart_CObject* object);
   bool IsCObjectMarked(Dart_CObject* object);
   intptr_t GetMarkedCObjectMark(Dart_CObject* object);
   void UnmarkAllCObjects(Dart_CObject* object);
 
@@ skipping 97 matching lines @@
 
  private:
   SnapshotWriter* writer_;
 
   DISALLOW_COPY_AND_ASSIGN(SnapshotWriterVisitor);
 };
 
 }  // namespace dart
 
 #endif  // VM_SNAPSHOT_H_