Differentiate primary account compares on GAIA cookie presence.

components/signin/core/browser/signin_metrics.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 COMPONENTS_SIGNIN_CORE_BROWSER_SIGNIN_METRICS_H_
 #define COMPONENTS_SIGNIN_CORE_BROWSER_SIGNIN_METRICS_H_
 
 namespace signin_metrics {
 
+// Enum for the ways in which primary account detection is done.
+enum DifferentPrimaryAccounts {
+  // token and cookie had same primary accounts.
+  ACCOUNTS_SAME = 0,
+  // Deprecated. Indicates different primary accounts.
+  UNUSED_ACCOUNTS_DIFFERENT,
+  // No GAIA cookie present, so the primaries are considered different.
+  NO_COOKIE_PRESENT,
+  // There was at least one cookie and one token, and the primaries differed.
+  COOKIE_AND_TOKEN_PRIMARIES_DIFFERENT,
+  NUM_DIFFERENT_PRIMARY_ACCOUNT_METRICS,
+};
+
 // Log to UMA histograms and UserCounts stats about a single execution of the
 // AccountReconciler.
 // |total_number_accounts| - How many accounts are in the browser for this
 //                           profile.
 // |count_added_to_cookie_jar| - How many accounts were in the browser but not
 //                               the cookie jar.
 // |count_added_to_token| - How may accounts were in the cookie jar but not in
 //                          the browser.
 // |primary_accounts_same| - False if the primary account for the cookie jar
 //                           and the token service were different; else true.
 // |is_first_reconcile| - True if these stats are from the first execution of
 //                        the AccountReconcilor.
+// |pre_count_gaia_cookies| - How many GAIA cookies were present before
+//                            the AccountReconcilor began modifying the state.
 void LogSigninAccountReconciliation(int total_number_accounts,
                                     int count_added_to_cookie_jar,
                                     int count_added_to_token,
                                     bool primary_accounts_same,
-                                    bool is_first_reconcile);
+                                    bool is_first_reconcile,
+                                    int pre_count_gaia_cookies);
 
 // Track a successful signin.
 void LogSigninAddAccount();
 
 }  // namespace signin_metrics
 
 #endif  // COMPONENTS_SIGNIN_CORE_BROWSER_SIGNIN_METRICS_H_