predictors: Collect page load metrics for ResourcePrefetchPredictor.

chrome/browser/predictors/resource_prefetch_predictor.h

 // Copyright 2014 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_RESOURCE_PREFETCH_PREDICTOR_H_
 #define CHROME_BROWSER_PREDICTORS_RESOURCE_PREFETCH_PREDICTOR_H_
 
 #include <stddef.h>
 
 #include <map>
@@ skipping 147 matching lines @@
   void StartPrefetching(const GURL& main_frame_url, PrefetchOrigin origin);
 
   // Stops prefetching that may be in progress corresponding to
   // |main_frame_url|.
   void StopPrefetching(const GURL& main_frame_url);
 
   // Called when ResourcePrefetcher is finished, i.e. there is nothing pending
   // in flight.
   void OnPrefetchingFinished(const GURL& main_frame_url);
 
+  // Returns true if prefetching data exists for the |main_frame_url|.
+  virtual bool IsUrlPrefetchable(const GURL& main_frame_url);
+
   // Sets the |observer| to be notified when the resource prefetch predictor
   // data changes. Previously registered observer will be discarded. Call
   // this with nullptr parameter to de-register observer.
   void SetObserverForTesting(TestObserver* observer);
 
  private:
   friend class ::PredictorsHandler;
   friend class ResourcePrefetchPredictorTest;
   friend class ResourcePrefetchPredictorBrowserTest;
 
@@ skipping 63 matching lines @@
   void OnMainFrameRedirect(const URLRequestSummary& response);
   void OnSubresourceResponse(const URLRequestSummary& response);
 
   // Called when onload completes for a navigation. We treat this point as the
   // "completion" of the navigation. The resources requested by the page up to
   // this point are the only ones considered for prefetching.
   void OnNavigationComplete(const NavigationID& nav_id_without_timing_info);
 
   // Returns true iff there is PrefetchData that can be used for a
   // |main_frame_url| and fills |urls| with resources that need to be
-  // prefetched.
-  bool GetPrefetchData(const GURL& main_frame_url, std::vector<GURL>* urls);
+  // prefetched. |urls| pointer may be equal nullptr to get return value only.
+  bool GetPrefetchData(const GURL& main_frame_url,
+                       std::vector<GURL>* urls) const;
 
   // Returns true iff the |data_map| contains PrefetchData that can be used
   // for a |main_frame_key| and fills |urls| with resources that need to be
-  // prefetched.
+  // prefetched. |urls| pointer may be equal nullptr to get return value only.
   bool PopulatePrefetcherRequest(const std::string& main_frame_key,
                                  const PrefetchDataMap& data_map,
-                                 std::vector<GURL>* urls);
+                                 std::vector<GURL>* urls) const;
 
   // Callback for task to read predictor database. Takes ownership of
   // all arguments.
   void CreateCaches(std::unique_ptr<PrefetchDataMap> url_data_map,
                     std::unique_ptr<PrefetchDataMap> host_data_map,
                     std::unique_ptr<RedirectDataMap> url_redirect_data_map,
                     std::unique_ptr<RedirectDataMap> host_redirect_data_map);
 
   // Called during initialization when history is read and the predictor
   // database has been read.
@@ skipping 34 matching lines @@
                        RedirectDataMap* redirect_map);
 
   // Updates information about final redirect destination for |key| in
   // |redirect_map| and correspondingly updates the predictor database.
   void LearnRedirect(const std::string& key,
                      PrefetchKeyType key_type,
                      const std::string& final_redirect,
                      size_t max_redirect_map_size,
                      RedirectDataMap* redirect_map);
 
-  // Returns true iff the |data_map| contains PrefetchData that can be used
-  // for |main_frame_key| prefetching.
-  bool IsDataPrefetchable(const std::string& main_frame_key,
-                          const PrefetchDataMap& data_map) const;
-
   // Returns true iff |resource| has sufficient confidence level and required
   // number of hits.
   bool IsResourcePrefetchable(const ResourceData& resource) const;
 
   // Reports database readiness metric defined as percentage of navigated hosts
   // found in DB for last X entries in history.
   void ReportDatabaseReadiness(const history::TopHostsList& top_hosts) const;
 
   // history::HistoryServiceObserver:
   void OnURLsDeleted(history::HistoryService* history_service,
@@ skipping 57 matching lines @@
 
  private:
   ResourcePrefetchPredictor* predictor_;
 
   DISALLOW_COPY_AND_ASSIGN(TestObserver);
 };
 
 }  // namespace predictors
 
 #endif  // CHROME_BROWSER_PREDICTORS_RESOURCE_PREFETCH_PREDICTOR_H_