Remove unnecesary usage of RefPtr and PassRefPtr of DatabaseContext.

Source/modules/webdatabase/DatabaseBackendSync.cpp

 /*
  * Copyright (C) 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 13 matching lines @@
  */
 
 #include "config.h"
 #include "modules/webdatabase/DatabaseBackendSync.h"
 
 #include "modules/webdatabase/DatabaseContext.h"
 #include "modules/webdatabase/DatabaseTracker.h"
 
 namespace WebCore {
 
-DatabaseBackendSync::DatabaseBackendSync(PassRefPtr<DatabaseContext> databaseContext, const String& name, const String& expectedVersion, const String& displayName, unsigned long estimatedSize)
+DatabaseBackendSync::DatabaseBackendSync(DatabaseContext* databaseContext, const String& name, const String& expectedVersion, const String& displayName, unsigned long estimatedSize)
     : DatabaseBackendBase(databaseContext, name, expectedVersion, displayName, estimatedSize, DatabaseType::Sync)
 {
 }
 
 DatabaseBackendSync::~DatabaseBackendSync()
 {
     // SQLite is "multi-thread safe", but each database handle can only be used
     // on a single thread at a time.
     //
     // For DatabaseBackendSync, we open the SQLite database on the script context
@@ skipping 10 matching lines @@
     DatabaseBackendBase::trace(visitor);
 }
 
 bool DatabaseBackendSync::openAndVerifyVersion(bool setVersionInNewDatabase, DatabaseError& error, String& errorMessage)
 {
     DatabaseTracker::tracker().prepareToOpenDatabase(this);
     return performOpenAndVerify(setVersionInNewDatabase, error, errorMessage);
 }
 
 } // namespace WebCore