Drop more dependencies of ProfileKeyedService infrastructure on chrome.

chrome/browser/predictors/predictor_database_factory.h

 // Copyright (c) 2012 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.
 
 #ifndef CHROME_BROWSER_PREDICTORS_PREDICTOR_DATABASE_FACTORY_H_
 #define CHROME_BROWSER_PREDICTORS_PREDICTOR_DATABASE_FACTORY_H_
 
 #include "base/basictypes.h"
 #include "base/memory/singleton.h"
 #include "chrome/browser/profiles/profile_keyed_service_factory.h"
 
+class Profile;
+
 namespace predictors {
 
 class PredictorDatabase;
 
 // Singleton that owns the PredictorDatabases and associates them with
 // Profiles.
 class PredictorDatabaseFactory : public ProfileKeyedServiceFactory {
  public:
   static PredictorDatabase* GetForProfile(Profile* profile);
 
   static PredictorDatabaseFactory* GetInstance();
 
  private:
   friend struct DefaultSingletonTraits<PredictorDatabaseFactory>;
 
   PredictorDatabaseFactory();
   virtual ~PredictorDatabaseFactory();
 
   // ProfileKeyedServiceFactory:
   virtual ProfileKeyedService* BuildServiceInstanceFor(
       content::BrowserContext* profile) const OVERRIDE;
 
   DISALLOW_COPY_AND_ASSIGN(PredictorDatabaseFactory);
 };
 
 }  // namespace predictors
 
 #endif  // CHROME_BROWSER_PREDICTORS_PREDICTOR_DATABASE_FACTORY_H_