Fix bug 5883:

runtime/bin/dbg_message.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 "bin/dbg_connection.h"
 #include "bin/dbg_message.h"
 #include "bin/dartutils.h"
 #include "bin/thread.h"
 #include "bin/utils.h"
 
@@ skipping 974 matching lines @@
 
 void DbgMsgQueueList::RemoveIsolateMsgQueue(Dart_IsolateId isolate_id) {
   MutexLocker ml(&msg_queue_list_lock_);
   if (list_ == NULL) {
     return;  // No items in the list.
   }
   DbgMsgQueue* queue = list_;
   if (queue->isolate_id() == isolate_id) {
     list_ = queue->next();  // Remove from list.
     delete queue;  // Delete the message queue.
+    return;
   } else {
     DbgMsgQueue* iterator = queue;
     queue = queue->next();
     while (queue != NULL) {
-      if (queue->isolate_id() != isolate_id) {
+      if (queue->isolate_id() == isolate_id) {
         iterator->set_next(queue->next());  // Remove from list.
         delete queue;  // Delete the message queue.
-        break;
+        return;
       }
       iterator = queue;
       queue = queue->next();
     }
   }
+  UNREACHABLE();
 }
 
 
 void DbgMsgQueueList::BptResolvedHandler(Dart_IsolateId isolate_id,
                                          intptr_t bp_id,
                                          Dart_Handle url,
                                          intptr_t line_number) {
   ASSERT(Dart_GetIsolate(isolate_id) == Dart_CurrentIsolate());
   Dart_EnterScope();
   dart::TextBuffer msg(128);
@@ skipping 53 matching lines @@
     msg_queue->SendIsolateEvent(isolate_id, kind);
     if (kind == kInterrupted) {
       msg_queue->HandleMessages();
     } else {
       ASSERT(kind == kShutdown);
       RemoveIsolateMsgQueue(isolate_id);
     }
   }
   Dart_ExitScope();
 }