VM: [Kernel] Revert changes to the native ports that introduced peers.

runtime/vm/native_message_handler.cc

Index: runtime/vm/native_message_handler.cc
diff --git a/runtime/vm/native_message_handler.cc b/runtime/vm/native_message_handler.cc
index baa073d69a3cc0c56365b204f4de61a10411030d..41fbd2cabc0ecafbf6c75db597e20290b94c65d7 100644
--- a/runtime/vm/native_message_handler.cc
+++ b/runtime/vm/native_message_handler.cc
@@ -12,9 +12,8 @@
 namespace dart {
 
 NativeMessageHandler::NativeMessageHandler(const char* name,
-                                           Dart_NativeMessageHandler func,
-                                           void* peer)
-    : name_(strdup(name)), func_(func), peer_(peer) {}
+                                           Dart_NativeMessageHandler func)
+    : name_(strdup(name)), func_(func) {}
 
 
 NativeMessageHandler::~NativeMessageHandler() {
@@ -42,7 +41,7 @@ MessageHandler::MessageStatus NativeMessageHandler::HandleMessage(
   Dart_CObject* object;
   ApiMessageReader reader(message);
   object = reader.ReadMessage();
-  (*func())(message->dest_port(), object, peer());
+  (*func())(message->dest_port(), object);
   delete message;
   return kOK;
 }