Adds a special case for sending an int over a port with the native API.

runtime/vm/service.cc

 // 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.
 
 #include "vm/service.h"
 
 #include "include/dart_api.h"
 #include "include/dart_native_api.h"
 #include "platform/globals.h"
 
@@ skipping 1427 matching lines @@
   if (!GetUnsignedIntegerId(parts[1], &message_id, 16)) {
     return Object::sentinel().raw();
   }
   MessageHandler::AcquiredQueues aq;
   thread->isolate()->message_handler()->AcquireQueues(&aq);
   Message* message = aq.queue()->FindMessageById(message_id);
   if (message == NULL) {
     // The user may try to load an expired message.
     return Object::sentinel().raw();
   }
-  MessageSnapshotReader reader(message->data(),
-                               message->len(),
-                               thread);
-  return reader.ReadObject();
+  if (message->len() > 0) {
+    MessageSnapshotReader reader(message->data(),
+                                 message->len(),
+                                 thread);
+    return reader.ReadObject();
+  } else {
+    return message->raw_obj();
+  }
 }
 
 
 static RawObject* LookupHeapObject(Thread* thread,
                                    const char* id_original,
                                    ObjectIdRing::LookupResult* result) {
   char* id = thread->zone()->MakeCopyOfString(id_original);
 
   // Parse the id by splitting at each '/'.
   const int MAX_PARTS = 8;
@@ skipping 2093 matching lines @@
     const ServiceMethodDescriptor& method = service_methods_[i];
     if (strcmp(method_name, method.name) == 0) {
       return &method;
     }
   }
   return NULL;
 }
 
 
 }  // namespace dart