Add Dart_PostPriority function to dart_api, and use it in runAsync to schedule immediate events in …

runtime/vm/message.h

 // Copyright (c) 2011, 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.
 
 #ifndef VM_MESSAGE_H_
 #define VM_MESSAGE_H_
 
 #include "vm/thread.h"
 
 // Duplicated from dart_api.h to avoid including the whole header.
 typedef int64_t Dart_Port;
 
 namespace dart {
 
 class Message {
  public:
   typedef enum {
     kNormalPriority = 0,  // Deliver message when idle.
-    kOOBPriority = 1,     // Deliver message asap.
-
-    // Iteration.
-    kFirstPriority = 0,
-    kNumPriorities = 2,
+    kFirstPriority = 1,   // Deliver message asap.

[Lasse Reichstein Nielsen, 2013/10/03 08:53:41]

asap->ASAP.

[floitsch, 2013/10/03 09:04:26]

Maybe just: Deliver message when idle before normal priority.

+    kOOBPriority = 2,     // Deliver message OOB.

[Lasse Reichstein Nielsen, 2013/10/03 08:53:41]

Spell out "Out-of-band", and say what it means. How is it different from "ASAP"?

   } Priority;
 
   // A port number which is never used.
   static const Dart_Port kIllegalPort = 0;
 
   // A new message to be sent between two isolates. The data handed to this
   // message will be disposed by calling free() once the message object is
   // being destructed (after delivery or when the receiving port is closed).
   //
   // If reply_port is kIllegalPort, then there is no reply port.
@@ skipping 50 matching lines @@
 
   Message* head_;
   Message* tail_;
 
   DISALLOW_COPY_AND_ASSIGN(MessageQueue);
 };
 
 }  // namespace dart
 
 #endif  // VM_MESSAGE_H_