[Smart Lock, Settings Reconciliation] Histograms for tracking initial and final pref values.

chrome/browser/password_manager/password_manager_setting_migrator_service.cc

Index: chrome/browser/password_manager/password_manager_setting_migrator_service.cc
diff --git a/chrome/browser/password_manager/password_manager_setting_migrator_service.cc b/chrome/browser/password_manager/password_manager_setting_migrator_service.cc
index 10797ec18bcdf6fd253d39ba59f01c23ba6d9d3a..67bca03a3cfcc3a6a3020d4b575046e68cb9063e 100644
--- a/chrome/browser/password_manager/password_manager_setting_migrator_service.cc
+++ b/chrome/browser/password_manager/password_manager_setting_migrator_service.cc
@@ -235,6 +235,25 @@ void PasswordManagerSettingMigratorService::MigrateAfterModelAssociation(
       UpdatePreferencesValues(prefs, false);
     }
   }
-  // TODO(melandory) Add histogram which will log combination of initial and
-  // final values for the both preferences.
+  bool final_new_pref_value =

[engedy, 2015/09/29 13:24:52]

nit: I would extract this into a separate method.

[melandory, 2015/09/29 22:08:38]

Done.

+      prefs->GetBoolean(password_manager::prefs::kCredentialsEnableService);
+  bool final_legacy_pref_value =
+      prefs->GetBoolean(password_manager::prefs::kPasswordManagerSavingEnabled);
+  const int kMaxInitValue = 0x10;
+  int value_to_log = 0;
+  const int kInitNewValueMask = 0x8;

[engedy, 2015/09/29 13:24:52]

nit: s/Init/Initial/, below too.

[melandory, 2015/09/29 22:08:38]

Done.

+  const int kInitLegacyValueMask = 0x4;
+  const int kFinalNewValueMask = 0x2;
+  const int kFinalLegacyValueMask = 0x1;
+  if (initial_new_pref_value_)
+    value_to_log |= kInitNewValueMask;
+  if (initial_legacy_pref_value_)
+    value_to_log |= kInitLegacyValueMask;
+  if (final_new_pref_value)
+    value_to_log |= kFinalNewValueMask;
+  if (final_legacy_pref_value)
+    value_to_log |= kFinalLegacyValueMask;
+  UMA_HISTOGRAM_ENUMERATION(
+      "PasswordManager.SettingsReconciliation.InitialAndFinalValues",
+      value_to_log, kMaxInitValue);
 }