Added incident report for variations seed signature mismatch.

chrome/browser/metrics/variations/variations_seed_store.h

Index: chrome/browser/metrics/variations/variations_seed_store.h
diff --git a/chrome/browser/metrics/variations/variations_seed_store.h b/chrome/browser/metrics/variations/variations_seed_store.h
index c81b15e3e0967def607055df822dd13cd7ed7371..64de29738928d528dcac58387c593a208ab9ee3b 100644
--- a/chrome/browser/metrics/variations/variations_seed_store.h
+++ b/chrome/browser/metrics/variations/variations_seed_store.h
@@ -10,6 +10,8 @@
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "base/time/time.h"
+#include "chrome/browser/safe_browsing/incident_reporting/add_incident_callback.h"

[grt (UTC plus 2), 2014/10/10 17:45:42]

remove these

[Georges Khalil, 2014/10/10 20:19:31]

Done.

+#include "chrome/browser/safe_browsing/safe_browsing_service.h"
 
 class PrefService;
 class PrefRegistrySimple;
@@ -55,6 +57,10 @@ class VariationsSeedStore {
   // Registers Local State prefs used by this class.
   static void RegisterPrefs(PrefRegistrySimple* registry);
 
+  // Returns the bad signature that was loaded from the config or an empty

[grt (UTC plus 2), 2014/10/10 17:45:42]

using the empty string like this overloads these cases:
- signature was valid
- signature verification is disabled
- signature value was expected but missing (VARIATIONS_SEED_SIGNATURE_MISSING)
this last case should result in a report being sent, so i think you need an
additional piece of state to disambiguate.

[Georges Khalil, 2014/10/10 20:19:31]

This is by design. We only want a report if the signature is invalid for now.

[grt (UTC plus 2), 2014/10/14 01:28:29]

Acknowledged.

+  // string if not the case. Used to send an incident report.

[grt (UTC plus 2), 2014/10/10 17:45:42]

omit " Used to send an incident report." since this comment will become stale if
another consumer comes around.

[Georges Khalil, 2014/10/10 20:19:31]

Done.

+  std::string GetBadSignature() const { return bad_signature_; }

[grt (UTC plus 2), 2014/10/10 17:45:42]

imo, "invalid" is better than "bad" for the function, doc, and variable name.

[Georges Khalil, 2014/10/10 20:19:31]

Done.

+
  protected:
   // Note: UMA histogram enum - don't re-order or remove entries.
   enum VerifySignatureResult {
@@ -82,6 +88,9 @@ class VariationsSeedStore {
   // Clears all prefs related to variations seed storage.
   void ClearPrefs();
 
+  // Keeps track of a bad signature.
+  std::string bad_signature_;
+
   // The pref service used to persist the variations seed.
   PrefService* local_state_;