Use the ThreadPool for all isolates and native ports. Previously,

runtime/vm/port.cc

 // 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.
 
 #include "vm/port.h"
 
 #include "platform/utils.h"
 #include "vm/dart_api_impl.h"
 #include "vm/isolate.h"
-#include "vm/message.h"
+#include "vm/message_handler.h"
 #include "vm/thread.h"
 
 namespace dart {
 
 DECLARE_FLAG(bool, trace_isolates);
 
 Mutex* PortMap::mutex_ = NULL;
 PortMap::Entry* PortMap::map_ = NULL;
 MessageHandler* PortMap::deleted_entry_ = reinterpret_cast<MessageHandler*>(1);
 intptr_t PortMap::capacity_ = 0;
@@ skipping 203 matching lines @@
   // TODO(iposva): Verify whether we want to keep exponentially growing.
   ASSERT(Utils::IsPowerOfTwo(kInitialCapacity));
   map_ = new Entry[kInitialCapacity];
   memset(map_, 0, kInitialCapacity * sizeof(Entry));
   capacity_ = kInitialCapacity;
   used_ = 0;
   deleted_ = 0;
 }
 
 }  // namespace dart