Change IllegalArgumentException to ArgumentError.

runtime/lib/isolate.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 "platform/assert.h"
 #include "vm/bootstrap_natives.h"
 #include "vm/class_finalizer.h"
 #include "vm/dart.h"
 #include "vm/dart_api_impl.h"
 #include "vm/dart_entry.h"
@@ skipping 134 matching lines @@
   PortMap::PostMessage(new Message(send_id.Value(), reply_id.Value(),
                                    data, writer.BytesWritten(),
                                    Message::kNormalPriority));
   return Object::null();
 }
 
 
 static void ThrowIllegalArgException(const String& message) {
   GrowableArray<const Object*> args(1);
   args.Add(&message);
-  Exceptions::ThrowByType(Exceptions::kIllegalArgument, args);
+  Exceptions::ThrowByType(Exceptions::kArgument, args);
 }
 
 
 static void ThrowIsolateSpawnException(const String& message) {
   GrowableArray<const Object*> args(1);
   args.Add(&message);
   Exceptions::ThrowByType(Exceptions::kIsolateSpawn, args);
 }
 
 
@@ skipping 272 matching lines @@
 
 DEFINE_NATIVE_ENTRY(isolate_getPortInternal, 0) {
   const Object& port = Object::Handle(ReceivePortCreate(isolate->main_port()));
   if (port.IsError()) {
     Exceptions::PropagateError(Error::Cast(port));
   }
   return port.raw();
 }
 
 }  // namespace dart