Add Rappor metrics for Safe Browsing and SSL interstitials.

chrome/browser/interstitials/security_interstitial_metrics_helper.h

 // Copyright (c) 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_INTERSTITIALS_SECURITY_INTERSTITIAL_UMA_HELPER_H_
-#define CHROME_BROWSER_INTERSTITIALS_SECURITY_INTERSTITIAL_UMA_HELPER_H_
+#ifndef CHROME_BROWSER_INTERSTITIALS_SECURITY_INTERSTITIAL_METRICS_HELPER_H_
+#define CHROME_BROWSER_INTERSTITIALS_SECURITY_INTERSTITIAL_METRICS_HELPER_H_
+
+#include <string>
 
 #include "base/task/cancelable_task_tracker.h"
 #include "base/time/time.h"
 #include "url/gurl.h"
 
 namespace content {
 class WebContents;
 }
 
 namespace extensions {
 class ExperienceSamplingEvent;
 }
 
 // Most of the security interstitials share a common layout and set of
-// choices. SecurityInterstitialUmaHelper is intended to help the security
-// interstitials record user choices in a common way via UMA histograms.
-class SecurityInterstitialUmaHelper {
+// choices. SecurityInterstitialMetricsHelper is intended to help the security
+// interstitials record user choices in a common way via METRICS histograms
+// and RAPPOR metrics.
+class SecurityInterstitialMetricsHelper {
  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 SecurityInterstitialDecision {
     SHOW,
     PROCEED,
     DONT_PROCEED,
     PROCEEDING_DISABLED,
     MAX_DECISION
   };
   enum SecurityInterstitialInteraction {
     TOTAL_VISITS,
     SHOW_ADVANCED,
     SHOW_PRIVACY_POLICY,
     SHOW_DIAGNOSTIC,
     SHOW_LEARN_MORE,
     RELOAD,
     OPEN_TIME_SETTINGS,
     MAX_INTERACTION
   };
 
-  SecurityInterstitialUmaHelper(content::WebContents* web_contents,
-                                const GURL& url,
-                                const std::string& histogram_prefix,
-                                const std::string& sampling_event_name);
-  ~SecurityInterstitialUmaHelper();
+  // Args:
+  //   url: URL of page that triggered the interstitial. Only origin is used.
+  //   uma_prefix: Histogram prefix for UMA.
+  //               examples: "phishing", "ssl_overridable"
+  //   rappor_prefix: Metric prefix for Rappor. Leave empty to skip Rappor.
+  //               examples: "phishing", "ssl"

[felt, 2015/02/03 07:28:04]

I'm a little uncomfortable about using a string status to determine whether
Rappor should be recorded or not. It feels brittle and like someone might get
this call wrong in the future by copying call sites and just putting the same
string in twice. Would it be a problem if we accidentally recorded Rappor
metrics for something we didn't mean to?

[Alexei Svitkine (slow), 2015/02/03 14:58:25]

Actually that's a good point.

If the prefixes will always be the same except in cases where we want to not log
RAPPOR, then I would prefer that there's a single prefix param and an enum that
specifies whether RAPPOR should be logged or not.

[Nathan Parker, 2015/02/03 21:01:00]

That would just muddle the reports in this case (report domains that aren't
related to the problem).

[Nathan Parker, 2015/02/03 21:01:00]

Sounds good.  I've made it far more explicit.

+  //   sampling_event_name: Event name for Experience Sampling.
+  //                        e.g. "phishing_interstitial_"
+  SecurityInterstitialMetricsHelper(content::WebContents* web_contents,
+                                    const GURL& url,
+                                    const std::string& uma_prefix,
+                                    const std::string& rappor_prefix,
+                                    const std::string& sampling_event_name);
+  ~SecurityInterstitialMetricsHelper();
 
-  // Record a user decision or interaction to the appropriate UMA histogram.
+  // Record a user decision or interaction to the appropriate UMA histogram
+  // and potentially in a RAPPOR metric.
   void RecordUserDecision(SecurityInterstitialDecision decision);
   void RecordUserInteraction(SecurityInterstitialInteraction interaction);
 
  private:
   // Used to query the HistoryService to see if the URL is in history.
   void OnGotHistoryCount(bool success, int num_visits, base::Time first_visit);
 
   content::WebContents* web_contents_;
   const GURL request_url_;
-  const std::string histogram_prefix_;
+  const std::string uma_prefix_;
+  const std::string rappor_prefix_;
   const std::string sampling_event_name_;
   int num_visits_;
   base::CancelableTaskTracker request_tracker_;
 #if defined(ENABLE_EXTENSIONS)
   scoped_ptr<extensions::ExperienceSamplingEvent> sampling_event_;
 #endif
 
-  DISALLOW_COPY_AND_ASSIGN(SecurityInterstitialUmaHelper);
+  DISALLOW_COPY_AND_ASSIGN(SecurityInterstitialMetricsHelper);
 };
 
-#endif  // CHROME_BROWSER_INTERSTITIALS_SECURITY_INTERSTITIAL_UMA_HELPER_H_
+#endif  // CHROME_BROWSER_INTERSTITIALS_SECURITY_INTERSTITIAL_METRICS_HELPER_H_