Revert "Hide Isolate pointer from embedder"

runtime/bin/dbg_connection.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/lockers.h"
 #include "bin/log.h"
 #include "bin/socket.h"
@@ skipping 437 matching lines @@
     handler->HandleMessages();
     delete handler;
   }
 }
 
 
 void DebuggerConnectionHandler::HandleInterruptCmd(DbgMessage* in_msg) {
   MessageParser msg_parser(in_msg->buffer(), in_msg->buffer_len());
   int msg_id = msg_parser.MessageId();
   Dart_IsolateId isolate_id = msg_parser.GetInt64Param("isolateId");
-  if (isolate_id == DART_ILLEGAL_ISOLATE_ID ||
-      Dart_GetIsolate(isolate_id) == DART_ILLEGAL_ISOLATE) {
+  if (isolate_id == ILLEGAL_ISOLATE_ID || Dart_GetIsolate(isolate_id) == NULL) {
     in_msg->SendErrorReply(msg_id, "Invalid isolate specified");
     return;
   }
   if (!DbgMsgQueueList::InterruptIsolate(isolate_id)) {
     in_msg->SendErrorReply(msg_id, "Invalid isolate specified");
     return;
   }
   dart::TextBuffer msg(64);
   msg.Printf("{ \"id\": %d }", msg_id);
   in_msg->SendReply(&msg);
@@ skipping 38 matching lines @@
 
 
 bool DebuggerConnectionHandler::IsConnected() {
   // TODO(asiva): Support multiple debugger connections.
   // Return true if a connection has been established.
   return singleton_handler != NULL;
 }
 
 }  // namespace bin
 }  // namespace dart