Relax zone allocation assertion

runtime/vm/thread.h

 // Copyright (c) 2015, 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_THREAD_H_
 #define VM_THREAD_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/atomic.h"
@@ skipping 241 matching lines @@
   void set_os_thread(OSThread* os_thread) {
     os_thread_ = os_thread;
   }
 
   // Monitor corresponding to this thread.
   Monitor* thread_lock() const { return thread_lock_; }
 
   // The topmost zone used for allocation in this thread.
   Zone* zone() const { return zone_; }
 
+  bool ZoneIsOwnedByThread(Zone* zone) const;
+
   // The reusable api local scope for this thread.
   ApiLocalScope* api_reusable_scope() const { return api_reusable_scope_; }
   void set_api_reusable_scope(ApiLocalScope* value) {
     ASSERT(value == NULL || api_reusable_scope_ == NULL);
     api_reusable_scope_ = value;
   }
 
   // The api local scope for this thread, this where all local handles
   // are allocated.
   ApiLocalScope* api_top_scope() const { return api_top_scope_; }
@@ skipping 506 matching lines @@
 // Disable thread interrupts.
 class DisableThreadInterruptsScope : public StackResource {
  public:
   explicit DisableThreadInterruptsScope(Thread* thread);
   ~DisableThreadInterruptsScope();
 };
 
 }  // namespace dart
 
 #endif  // VM_THREAD_H_