Fix build

runtime/vm/timeline.cc

 // Copyright (c) 2015, 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 <cstdlib>
 
 #include "vm/atomic.h"
 #include "vm/isolate.h"
 #include "vm/json_stream.h"
 #include "vm/lockers.h"
@@ skipping 403 matching lines @@
       UNIMPLEMENTED();
   }
   {
     JSONObject args(&obj, "args");
     for (intptr_t i = 0; i < arguments_length_; i++) {
       const TimelineEventArgument& arg = arguments_[i];
       args.AddProperty(arg.name, arg.value);
     }
     if (isolate_id_ != ILLEGAL_PORT) {
       // If we have one, append the isolate id.
-      args.AddProperty("isolateNumber", isolate_id_);
+      args.AddPropertyF("isolateNumber", "%" Pd64 "",
+                        static_cast<int64_t>(isolate_id_));
     }
   }
 }
 
 
 int64_t TimelineEvent::TimeOrigin() const {
   return timestamp0_;
 }
 
 
@@ skipping 695 matching lines @@
 
 
 TimelineEventBlock* TimelineEventBlockIterator::Next() {
   ASSERT(current_ != NULL);
   TimelineEventBlock* r = current_;
   current_ = current_->next();
   return r;
 }
 
 }  // namespace dart