Ensure that the ThreadInterrupter is awake after debugging

runtime/vm/message_handler.cc

 // 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.
 
 #include "vm/message_handler.h"
 
 #include "vm/dart.h"
 #include "vm/lockers.h"
 #include "vm/port.h"
+#include "vm/thread_interrupter.h"
 
 namespace dart {
 
 DECLARE_FLAG(bool, trace_isolates);
 DECLARE_FLAG(bool, trace_service_pause_events);
 
 class MessageHandlerTask : public ThreadPool::Task {
  public:
   explicit MessageHandlerTask(MessageHandler* handler)
       : handler_(handler) {
@@ skipping 118 matching lines @@
   }
   return message;
 }
 
 
 bool MessageHandler::HandleMessages(bool allow_normal_messages,
                                     bool allow_multiple_normal_messages) {
   // If isolate() returns NULL StartIsolateScope does nothing.
   StartIsolateScope start_isolate(isolate());
 
+  // ThreadInterrupter may have gone to sleep waiting while waiting for
+  // an isolate to start handling messages.
+  ThreadInterrupter::WakeUp();
+
   // TODO(turnidge): Add assert that monitor_ is held here.
   bool result = true;
   Message::Priority min_priority = (allow_normal_messages && !paused()) ?
       Message::kNormalPriority : Message::kOOBPriority;
   Message* message = DequeueMessage(min_priority);
   while (message != NULL) {
     intptr_t message_len = message->len();
     if (FLAG_trace_isolates) {
       OS::Print("[<] Handling message:\n"
                 "\tlen:        %" Pd "\n"
@@ skipping 208 matching lines @@
 
 
 void MessageHandler::AcquireQueues(AcquiredQueues* acquired_queues) {
   ASSERT(acquired_queues != NULL);
   // No double dipping.
   ASSERT(acquired_queues->handler_ == NULL);
   acquired_queues->Reset(this);
 }
 
 }  // namespace dart