predictors: Add precision / recall histograms for speculative prefetch.

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 20 matching lines @@
 
 class PredictorsHandler;
 class Profile;
 
 namespace net {
 class URLRequest;
 }
 
 namespace predictors {
 
+namespace internal {
+constexpr char kResourcePrefetchPredictorPrecisionHistogram[] =
+    "ResourcePrefetchPredictor.LearningPrecision";
+constexpr char kResourcePrefetchPredictorRecallHistogram[] =
+    "ResourcePrefetchPredictor.LearningRecall";
+}  // namespace internal
+
 class TestObserver;
 class ResourcePrefetcherManager;
 
 // Contains logic for learning what can be prefetched and for kicking off
 // speculative prefetching.
 // - The class is a profile keyed service owned by the profile.
 // - All the non-static methods of this class need to be called on the UI
 //   thread.
 //
 // The overall flow of the resource prefetching algorithm is as follows:
@@ skipping 140 matching lines @@
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest, OnMainFrameRequest);
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest, OnMainFrameRedirect);
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest,
                            OnSubresourceResponse);
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest, GetCorrectPLT);
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest, HandledResourceTypes);
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest,
                            PopulatePrefetcherRequest);
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest, GetRedirectEndpoint);
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest, GetPrefetchData);
+  FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest,
+                           TestPrecisionRecallHistograms);
 
   enum InitializationState {
     NOT_INITIALIZED = 0,
     INITIALIZING = 1,
     INITIALIZED = 2
   };
 
   typedef ResourcePrefetchPredictorTables::PrefetchDataMap PrefetchDataMap;
   typedef ResourcePrefetchPredictorTables::RedirectDataMap RedirectDataMap;
 
@@ skipping 175 matching lines @@
 
  private:
   ResourcePrefetchPredictor* predictor_;
 
   DISALLOW_COPY_AND_ASSIGN(TestObserver);
 };
 
 }  // namespace predictors
 
 #endif  // CHROME_BROWSER_PREDICTORS_RESOURCE_PREFETCH_PREDICTOR_H_