Remove unnecesary usage of RefPtr and PassRefPtr of DatabaseContext.

Source/modules/webdatabase/DatabaseManager.h

 /*
  * Copyright (C) 2012 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 37 matching lines @@
 class SecurityOrigin;
 class ExecutionContext;
 
 typedef int ExceptionCode;
 
 class DatabaseManager {
     WTF_MAKE_NONCOPYABLE(DatabaseManager); WTF_MAKE_FAST_ALLOCATED;
 public:
     static DatabaseManager& manager();
 
-    // This gets a DatabaseContext for the specified ExecutionContext.
-    // If one doesn't already exist, it will create a new one.
-    PassRefPtr<DatabaseContext> databaseContextFor(ExecutionContext*);
-
     // These 2 methods are for DatabaseContext (un)registration, and should only
     // be called by the DatabaseContext constructor and destructor.
     void registerDatabaseContext(DatabaseContext*);
     void unregisterDatabaseContext(DatabaseContext*);
 
 #if !ASSERT_DISABLED
     void didConstructDatabaseContext();
     void didDestructDatabaseContext();
 #else
     void didConstructDatabaseContext() { }
     void didDestructDatabaseContext() { }
 #endif
 
     static void throwExceptionForDatabaseError(DatabaseError, const String& errorMessage, ExceptionState&);
 
     PassRefPtrWillBeRawPtr<Database> openDatabase(ExecutionContext*, const String& name, const String& expectedVersion, const String& displayName, unsigned long estimatedSize, PassOwnPtr<DatabaseCallback>, DatabaseError&, String& errorMessage);
     PassRefPtrWillBeRawPtr<DatabaseSync> openDatabaseSync(ExecutionContext*, const String& name, const String& expectedVersion, const String& displayName, unsigned long estimatedSize, PassOwnPtr<DatabaseCallback>, DatabaseError&, String& errorMessage);
 
     String fullPathForDatabase(SecurityOrigin*, const String& name, bool createIfDoesNotExist = true);
 
     void closeDatabasesImmediately(const String& originIdentifier, const String& name);
 
     void interruptAllDatabasesForContext(DatabaseContext*);
 
 private:
     DatabaseManager();
     ~DatabaseManager() { }
 
+    // This gets a DatabaseContext for the specified ExecutionContext.
+    // If one doesn't already exist, it will create a new one.
+    DatabaseContext* databaseContextFor(ExecutionContext*);
     // This gets a DatabaseContext for the specified ExecutionContext if
     // it already exist previously. Otherwise, it returns 0.
-    PassRefPtr<DatabaseContext> existingDatabaseContextFor(ExecutionContext*);
+    DatabaseContext* existingDatabaseContextFor(ExecutionContext*);
 
     PassRefPtrWillBeRawPtr<DatabaseBackendBase> openDatabaseBackend(ExecutionContext*,
         DatabaseType, const String& name, const String& expectedVersion, const String& displayName,
         unsigned long estimatedSize, bool setVersionInNewDatabase, DatabaseError&, String& errorMessage);
 
     static void logErrorMessage(ExecutionContext*, const String& message);
 
     AbstractDatabaseServer* m_server;
 
     // Access to the following fields require locking m_contextMapLock:
     typedef HashMap<ExecutionContext*, DatabaseContext*> ContextMap;
     ContextMap m_contextMap;
 #if !ASSERT_DISABLED
     int m_databaseContextRegisteredCount;
     int m_databaseContextInstanceCount;
 #endif
     Mutex m_contextMapLock;
 };
 
 } // namespace WebCore
 
 #endif // DatabaseManager_h