CrossThreadPersistent invalidation: add missing orphaned check.

Source/platform/heap/PersistentNode.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "platform/heap/PersistentNode.h"
 
 #include "platform/heap/Handle.h"
 
 namespace blink {
@@ skipping 101 matching lines @@
                 continue;
 
             // 'self' is in use, containing the cross-thread persistent wrapper object.
             CrossThreadPersistent<GCObject>* persistent = reinterpret_cast<CrossThreadPersistent<GCObject>*>(slots->m_slot[i].self());
             ASSERT(persistent);
             void* rawObject = persistent->get();
             if (!rawObject)
                 continue;
             BasePage* page = pageFromObject(rawObject);
             ASSERT(page);
+            // The main thread will upon detach just mark its heap pages as orphaned,
+            // but not invalidate its CrossThreadPersistent<>s.
+            if (page->orphaned())
+                continue;
             if (page->heap()->threadState() == threadState)

[haraken, 2015/08/05 14:22:33]

ah, page->heap() should be null for already orphaned pages.

                 persistent->clear();
         }
         slots = slots->m_next;
     }
 }
 
 } // namespace blink