Implement WebThreadSupportingGC, which wraps a WebThread attached to Oilpan's GC

Source/modules/webdatabase/DatabaseThread.cpp

 /*
  * Copyright (C) 2007, 2008, 2013 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 54 matching lines @@
 #if ENABLE(OILPAN)
     visitor->trace(m_openDatabaseSet);
     visitor->trace(m_transactionCoordinator);
 #endif
 }
 
 void DatabaseThread::start()
 {
     if (m_thread)
         return;
-    m_thread = adoptPtr(blink::Platform::current()->createThread("WebCore: Database"));
+    m_thread = WebThreadSupportingGC::create("WebCore: Database");
     m_thread->postTask(new Task(WTF::bind(&DatabaseThread::setupDatabaseThread, this)));
 }
 
 void DatabaseThread::setupDatabaseThread()
 {
-    m_pendingGCRunner = adoptPtr(new PendingGCRunner);
-    m_messageLoopInterruptor = adoptPtr(new MessageLoopInterruptor(m_thread.get()));
-    m_thread->addTaskObserver(m_pendingGCRunner.get());
-    ThreadState::attach();
-    ThreadState::current()->addInterruptor(m_messageLoopInterruptor.get());
+    m_thread->attachGC();
 }
 
 void DatabaseThread::requestTermination(TaskSynchronizer *cleanupSync)
 {
     MutexLocker lock(m_terminationRequestedMutex);
     ASSERT(!m_terminationRequested);
     m_terminationRequested = true;
     m_cleanupSync = cleanupSync;
     WTF_LOG(StorageAPI, "DatabaseThread %p was asked to terminate\n", this);
     m_thread->postTask(new Task(WTF::bind(&DatabaseThread::cleanupDatabaseThread, this)));
@@ skipping 26 matching lines @@
         WillBeHeapHashSet<RefPtrWillBeMember<DatabaseBackend> >::iterator end = openSetCopy.end();
         for (WillBeHeapHashSet<RefPtrWillBeMember<DatabaseBackend> >::iterator it = openSetCopy.begin(); it != end; ++it)
             (*it)->close();
     }
 
     m_thread->postTask(new Task(WTF::bind(&DatabaseThread::cleanupDatabaseThreadCompleted, this)));
 }
 
 void DatabaseThread::cleanupDatabaseThreadCompleted()
 {
-    ThreadState::current()->removeInterruptor(m_messageLoopInterruptor.get());
-    ThreadState::detach();
-    // We need to unregister PendingGCRunner before finising this task to avoid
-    // PendingGCRunner::didProcessTask accesses dead ThreadState.
-    m_thread->removeTaskObserver(m_pendingGCRunner.get());
-
+    m_thread->detachGC();
     if (m_cleanupSync) // Someone wanted to know when we were done cleaning up.
         m_cleanupSync->taskCompleted();
 }
 
 void DatabaseThread::recordDatabaseOpen(DatabaseBackend* database)
 {
     ASSERT(isDatabaseThread());
     ASSERT(database);
     ASSERT(!m_openDatabaseSet.contains(database));
     m_openDatabaseSet.add(database);
@@ skipping 17 matching lines @@
 
 void DatabaseThread::scheduleTask(PassOwnPtr<DatabaseTask> task)
 {
     ASSERT(m_thread);
     ASSERT(!task->hasSynchronizer() || task->hasCheckedForTermination());
     // WebThread takes ownership of the task.
     m_thread->postTask(task.leakPtr());
 }
 
 } // namespace blink