Make sure that Dart_Ports are printed safely in the service protocol

runtime/vm/isolate.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/isolate.h"
 
 #include "include/dart_api.h"
 #include "include/dart_native_api.h"
 #include "platform/assert.h"
 #include "platform/json.h"
@@ skipping 1812 matching lines @@
     default:
       UNIMPLEMENTED();
       return NULL;
   }
 }
 
 
 void Isolate::PrintJSON(JSONStream* stream, bool ref) {
   JSONObject jsobj(stream);
   jsobj.AddProperty("type", (ref ? "@Isolate" : "Isolate"));
-  jsobj.AddFixedServiceId("isolates/%" Pd "",
-                          static_cast<intptr_t>(main_port()));
+  jsobj.AddFixedServiceId("isolates/%" Pd64 "",
+                          static_cast<int64_t>(main_port()));
 
   jsobj.AddProperty("name", debugger_name());
-  jsobj.AddPropertyF("number", "%" Pd "",
-                     static_cast<intptr_t>(main_port()));
+  jsobj.AddPropertyF("number", "%" Pd64 "",
+                     static_cast<int64_t>(main_port()));
   if (ref) {
     return;
   }
-  jsobj.AddPropertyF("_originNumber", "%" Pd "",
-                     static_cast<intptr_t>(origin_id()));
+  jsobj.AddPropertyF("_originNumber", "%" Pd64 "",
+                     static_cast<int64_t>(origin_id()));
   int64_t start_time_millis = start_time() / kMicrosecondsPerMillisecond;
   jsobj.AddPropertyTimeMillis("startTime", start_time_millis);
   {
     JSONObject jsheap(&jsobj, "_heaps");
     heap()->PrintToJSONObject(Heap::kNew, &jsheap);
     heap()->PrintToJSONObject(Heap::kOld, &jsheap);
   }
 
   jsobj.AddProperty("livePorts", message_handler()->live_ports());
   jsobj.AddProperty("pauseOnExit", message_handler()->pause_on_exit());
@@ skipping 748 matching lines @@
                            serialized_message_, serialized_message_len_);
 }
 
 
 void IsolateSpawnState::Cleanup() {
   SwitchIsolateScope switch_scope(I);
   Dart::ShutdownIsolate();
 }
 
 }  // namespace dart