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

runtime/vm/service_test.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 "platform/globals.h"
 
 #include "include/dart_tools_api.h"
 #include "vm/dart_api_impl.h"
 #include "vm/dart_entry.h"
 #include "vm/debugger.h"
@@ skipping 17 matching lines @@
   ~ServiceTestMessageHandler() {
     free(_msg);
   }
 
   MessageStatus HandleMessage(Message* message) {
     if (_msg != NULL) {
       free(_msg);
     }
 
     // Parse the message.
+    EXPECT_GT(message->len(), 0);
     Thread* thread = Thread::Current();
     MessageSnapshotReader reader(message->data(), message->len(), thread);
     const Object& response_obj = Object::Handle(reader.ReadObject());
     String& response = String::Handle();
     response ^= response_obj.raw();
     _msg = strdup(response.ToCString());
     return kOK;
   }
 
   const char* msg() const { return _msg; }
@@ skipping 580 matching lines @@
       Eval(lib, "[0, port, '0', '_getCpuProfile', ['tags'], ['Bogus']]");
   Service::HandleIsolateMessage(isolate, service_msg);
   EXPECT_EQ(MessageHandler::kOK, handler.HandleNextMessage());
   // Expect error.
   EXPECT_SUBSTRING("\"error\"", handler.msg());
 }
 
 #endif  // !defined(TARGET_ARCH_ARM64)
 
 }  // namespace dart