android: move ResourcePrefetchPredictor usage to LoadingPredictor.

chrome/browser/predictors/loading_predictor.h

 // Copyright 2017 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_LOADING_PREDICTOR_H_
 #define CHROME_BROWSER_PREDICTORS_LOADING_PREDICTOR_H_
 
 #include <memory>
 
 #include "base/memory/weak_ptr.h"
@@ skipping 21 matching lines @@
   LoadingPredictor(const LoadingPredictorConfig& config, Profile* profile);
   ~LoadingPredictor() override;
 
   // Hints that a page load is expected for |url|, with the hint coming from a
   // given |origin|. May trigger actions, such as prefetch and/or preconnect.
   void PrepareForPageLoad(const GURL& url, HintOrigin origin);
 
   // Indicates that a page load hint is no longer active.
   void CancelPageLoadHint(const GURL& url);
 
+  // Starts initialization, will complete asynchronously.
+  void StartInitialization();
+
   // Don't use, internal only.
   ResourcePrefetchPredictor* resource_prefetch_predictor() const;
 
   // KeyedService:
   void Shutdown() override;
 
  private:
   std::unique_ptr<ResourcePrefetchPredictor> resource_prefetch_predictor_;
 
   DISALLOW_COPY_AND_ASSIGN(LoadingPredictor);
 };
 
 }  // namespace predictors
 
 #endif  // CHROME_BROWSER_PREDICTORS_LOADING_PREDICTOR_H_