Add a low-frequency RAPPOR configuration, and use it for Safe Browsing and Permissions metrics.

components/security_interstitials/core/metrics_helper.h

 // Copyright 2015 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 COMPONENTS_SECURITY_INTERSTITIALS_CORE_METRICS_HELPER_H_
 #define COMPONENTS_SECURITY_INTERSTITIALS_CORE_METRICS_HELPER_H_
 
 #include <string>
 
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/task/cancelable_task_tracker.h"
 #include "base/time/time.h"
 #include "components/rappor/rappor_service.h"
 #include "url/gurl.h"
 
 namespace history {
 class HistoryService;
 }
 
 namespace security_interstitials {
 
 // MetricsHelper records user warning interactions in a common way via METRICS
-// histograms and, optionally, RAPPOR metrics. The  class will generate the
+// histograms and, optionally, RAPPOR metrics. The class will generate the
 // following histograms:
 //   METRICS: interstitial.<metric_prefix>.decision[.repeat_visit]
 //   METRICS: interstitial.<metric_prefix>.interaction[.repeat_visi]
-//   RAPPOR:  interstitial.<rappor_prefix>
+//   RAPPOR:  interstitial.<rappor_prefix> (SafeBrowsing parameters)
+//   RAPPOR:  interstitial.<rappor_prefix>2 (Low frequency parameters)
 // wherein |metric_prefix| and |rappor_prefix| are specified via ReportDetails.
 // repeat_visit is also generated if the user has seen the page before.
 //
 // If |extra_suffix| is not empty, MetricsHelper will append ".<extra_suffix>"
 // to generate an additional 2 or 4 more metrics.
 class MetricsHelper {
  public:
   // These enums are used for histograms.  Don't reorder, delete, or insert
   // elements. New elements should be added at the end (right before the max).
   enum Decision {
@@ skipping 17 matching lines @@
     REPORT_PHISHING_ERROR,
     MAX_INTERACTION
   };
 
   // metric_prefix: Histogram prefix for UMA.
   //                examples: "phishing", "ssl_overridable"
   // extra_suffix: If not-empty, will generate second set of metrics by
   //               placing at the end of the metric name.  Examples:
   //               "from_datasaver", "from_device"
   // rappor_prefix: Metric prefix for Rappor.
-  //                examples: "phishing", "ssl2"
-  // rappor_report_type: Used to differentiate UMA and Safe Browsing statistics.
+  //                examples: "phishing2", "ssl3"
+  // rappor_report_type: Specifies the low-frequency RAPPOR configuration to use
+  // (i.e. UMA or Safe Browsing).

[tsergeant, 2016/04/26 04:40:51]

Nit: Align this line with the colon, like above.

[dominickn, 2016/04/26 09:44:30]

Done.

+  // deprecated_rappor_report_type: Specifies the deprecated RAPPOR
+  // configuration to use for comparison with the low-frequency metric.
   // The rappor preferences can be left blank if rappor_service is not set.
+  // TODO(dominickn): remove deprecated_rappor_report_type once sufficient
+  // comparison data has been collected and analysed - crbug.com/605836.
   struct ReportDetails {
     ReportDetails();
     ReportDetails(const ReportDetails& other);
+    ~ReportDetails();
     std::string metric_prefix;
     std::string extra_suffix;
     std::string rappor_prefix;
+    std::string deprecated_rappor_prefix;
     rappor::RapporType rappor_report_type;
+    rappor::RapporType deprecated_rappor_report_type;
   };
 
   // Args:
   //   url: URL of page that triggered the interstitial. Only origin is used.
   //   history_service: Set this to record metrics based on whether the user
   //                    has visited this hostname before.
   //   rappor_service: If you want RAPPOR statistics, provide a service,
   //                   settings.rappor_prefix, and settings.rappor_report_type.
   //   settings: Specify reporting details (prefixes and report types).
   //   sampling_event_name: Event name for Experience Sampling.
@@ skipping 20 matching lines @@
   virtual void RecordExtraUserInteractionMetrics(Interaction interaction) = 0;
   virtual void RecordExtraShutdownMetrics() = 0;
 
  private:
   // Used to query the HistoryService to see if the URL is in history.  It will
   // only be invoked if the constructor received |history_service|.
   void OnGotHistoryCount(bool success, int num_visits, base::Time first_visit);
 
   void RecordUserDecisionToMetrics(Decision decision,
                                    const std::string& histogram_name);
-  void RecordUserDecisionToRappor(Decision decision);
+  void RecordUserDecisionToRappor(Decision decision,
+                                  const rappor::RapporType rappor_report_type,
+                                  const std::string& rappor_prefix);
   const GURL request_url_;
   const ReportDetails settings_;
   base::WeakPtr<rappor::RapporService> rappor_service_;
   int num_visits_;
   base::CancelableTaskTracker request_tracker_;
 
   DISALLOW_COPY_AND_ASSIGN(MetricsHelper);
 };
 
 }  // namespace security_interstitials
 
 #endif  // COMPONENTS_SECURITY_INTERSTITIALS_CORE_METRICS_HELPER_H_