Create LoadingDataCollector class and have observers rely on it instead of ResourcePrefetchPredictor

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 <map>
 #include <memory>
 #include <utility>
 
 #include "base/gtest_prod_util.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
+#include "chrome/browser/predictors/loading_data_collector.h"
 #include "chrome/browser/predictors/resource_prefetch_common.h"
 #include "chrome/browser/predictors/resource_prefetch_predictor.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "url/gurl.h"
 
 class Profile;
 
 namespace predictors {
 
 class ResourcePrefetchPredictor;
@@ skipping 20 matching lines @@
   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   // Indicates that a page load hint is no longer active.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;
+  LoadingDataCollector* loading_data_collector() const;
 
   // KeyedService:
   void Shutdown() override;
 
   void OnMainFrameRequest(
       const ResourcePrefetchPredictor::URLRequestSummary& summary);
   void OnMainFrameRedirect(
       const ResourcePrefetchPredictor::URLRequestSummary& summary);
   void OnMainFrameResponse(
       const ResourcePrefetchPredictor::URLRequestSummary& summary);
 
  private:
   // Cancels an active hint, from its iterator inside |active_hints_|. If the
   // iterator is .end(), does nothing. Returns the iterator after deletion of
   // the entry.
   std::map<GURL, base::TimeTicks>::iterator CancelActiveHint(
       std::map<GURL, base::TimeTicks>::iterator hint_it);
   void CleanupAbandonedHintsAndNavigations(const NavigationID& navigation_id);
 
   // For testing.
   void set_mock_resource_prefetch_predictor(
       std::unique_ptr<ResourcePrefetchPredictor> predictor) {
     resource_prefetch_predictor_ = std::move(predictor);
   }
 
   LoadingPredictorConfig config_;
   Profile* profile_;
   std::unique_ptr<ResourcePrefetchPredictor> resource_prefetch_predictor_;
+  std::unique_ptr<LoadingDataCollector> loading_data_collector_;
   std::map<GURL, base::TimeTicks> active_hints_;
   // Initial URL.
   std::map<NavigationID, GURL> active_navigations_;
 
   friend class LoadingPredictorTest;
   FRIEND_TEST_ALL_PREFIXES(LoadingPredictorTest,
                            TestMainFrameResponseCancelsHint);
   FRIEND_TEST_ALL_PREFIXES(LoadingPredictorTest,
                            TestMainFrameRequestCancelsStaleNavigations);
   FRIEND_TEST_ALL_PREFIXES(LoadingPredictorTest,
                            TestMainFrameResponseClearsNavigations);
   FRIEND_TEST_ALL_PREFIXES(LoadingPredictorTest,
                            TestMainFrameRequestDoesntCancelExternalHint);
   FRIEND_TEST_ALL_PREFIXES(LoadingPredictorTest,
                            TestDontTrackNonPrefetchableUrls);
 
   DISALLOW_COPY_AND_ASSIGN(LoadingPredictor);
 };
 
 }  // namespace predictors
 
 #endif  // CHROME_BROWSER_PREDICTORS_LOADING_PREDICTOR_H_