Refactor the Heap into ThreadHeap to prepare for per thread heaps

third_party/WebKit/Source/modules/webdatabase/DatabaseTask.h

 /*
  * 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 26 matching lines @@
 #include "platform/TaskSynchronizer.h"
 #include "platform/heap/Handle.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/Threading.h"
 #include "wtf/Vector.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
+// DatabaseTask can be created from main thread and database thread.

[haraken, 2016/01/07 08:06:21]

from main thread => by the main thread

 class DatabaseTask {
     WTF_MAKE_NONCOPYABLE(DatabaseTask); USING_FAST_MALLOC(DatabaseTask);
 public:
     virtual ~DatabaseTask();
 
     void run();
 
     Database* database() const { return m_database.get(); }
 #if ENABLE(ASSERT)
     bool hasSynchronizer() const { return m_synchronizer; }
 #endif
 
 protected:
     DatabaseTask(Database*, TaskSynchronizer*);
 
 private:
     virtual void doPerformTask() = 0;
     virtual void taskCancelled() { }
 
-    CrossThreadPersistent<Database> m_database;
+    XThreadPersistent<Database> m_database;
     TaskSynchronizer* m_synchronizer;
 
 #if !LOG_DISABLED
     virtual const char* debugTaskName() const = 0;
     bool m_complete;
 #endif
 };
 
 class Database::DatabaseOpenTask final : public DatabaseTask {
 public:
@@ skipping 46 matching lines @@
 
 private:
     explicit DatabaseTransactionTask(SQLTransactionBackend*);
 
     void doPerformTask() override;
     void taskCancelled() override;
 #if !LOG_DISABLED
     const char* debugTaskName() const override;
 #endif
 
-    CrossThreadPersistent<SQLTransactionBackend> m_transaction;
+    XThreadPersistent<SQLTransactionBackend> m_transaction;
 };
 
 class Database::DatabaseTableNamesTask final : public DatabaseTask {
 public:
     static PassOwnPtr<DatabaseTableNamesTask> create(Database* db, TaskSynchronizer* synchronizer, Vector<String>& names)
     {
         return adoptPtr(new DatabaseTableNamesTask(db, synchronizer, names));
     }
 
 private:
     DatabaseTableNamesTask(Database*, TaskSynchronizer*, Vector<String>& names);
 
     void doPerformTask() override;
 #if !LOG_DISABLED
     const char* debugTaskName() const override;
 #endif
 
     Vector<String>& m_tableNames;
 };
 
 } // namespace blink
 
 #endif // DatabaseTask_h