Fix for use-after-free of reload context

runtime/vm/isolate.h

 // Copyright (c) 2013, 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_ISOLATE_H_
 #define VM_ISOLATE_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/atomic.h"
@@ skipping 237 matching lines @@
       const uint8_t* instructions_snapshot_buffer);
   void SetupDataSnapshotPage(
       const uint8_t* instructions_snapshot_buffer);
 
   void ScheduleMessageInterrupts();
 
   // Marks all libraries as loaded.
   void DoneLoading();
   void DoneFinalizing();
 
-  void ReloadSources(bool test_mode = false);
+  // By default the reload context is deleted. This parameter allows
+  // the caller to delete is separately if it is still needed.
+  void ReloadSources(bool dont_delete_reload_context = false);
 
   bool MakeRunnable();
   void Run();
 
   MessageHandler* message_handler() const { return message_handler_; }
   void set_message_handler(MessageHandler* value) { message_handler_ = value; }
 
   bool is_runnable() const { return is_runnable_; }
   void set_is_runnable(bool value) {
     is_runnable_ = value;
@@ skipping 204 matching lines @@
   }
 
   bool IsReloading() const {
     return reload_context_ != NULL;
   }
 
   IsolateReloadContext* reload_context() {
     return reload_context_;
   }
 
+  void DeleteReloadContext();
+
   bool HasAttemptedReload() const {
     return has_attempted_reload_;
   }
 
   bool CanReload() const;
 
   void ReportReloadError(const Error& error);
 
   uword user_tag() const {
     return user_tag_;
@@ skipping 497 matching lines @@
   intptr_t* spawn_count_;
 
   Dart_IsolateFlags isolate_flags_;
   bool paused_;
   bool errors_are_fatal_;
 };
 
 }  // namespace dart
 
 #endif  // VM_ISOLATE_H_