[Autofill] Log the number of profiles considered/removed during dedupe.

components/autofill/core/browser/personal_data_manager.cc

 // Copyright 2013 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.
 
 #include "components/autofill/core/browser/personal_data_manager.h"
 
 #include <stddef.h>
 #include <algorithm>
 #include <list>
 #include <map>
@@ skipping 1542 matching lines @@
   // Delete the duplicate profiles.
   for (const std::string& profile_guid_to_delete : profile_guids_to_delete) {
     RemoveByGUID(profile_guid_to_delete);
   }
 }
 
 void PersonalDataManager::FindAndMergeDuplicateProfiles(
     const std::vector<AutofillProfile*>& existing_profiles,
     AutofillProfile* profile_to_merge,
     std::vector<std::string>* profile_guids_to_delete) {
+  AutofillMetrics::LogNumberOfProfilesConsideredForDedupe(
+      existing_profiles.size());
   for (AutofillProfile* existing_profile : existing_profiles) {
     // Don't try to merge a profile with itself or with any profile with a
     // different PrimaryValue.
     if (existing_profile->guid() != profile_to_merge->guid() &&
         AutofillProfile::CanonicalizeProfileString(
             existing_profile->PrimaryValue(app_locale_)) ==
             AutofillProfile::CanonicalizeProfileString(
                 profile_to_merge->PrimaryValue(app_locale_))) {
       if (existing_profile->SaveAdditionalInfo(*profile_to_merge,
                                                app_locale_)) {
         // Since |profile_to_merge| was a duplicate of |existing_profile| and
         // was merged sucessfully, it can now be deleted.
         profile_guids_to_delete->push_back(profile_to_merge->guid());
 
         // Now try to merge the new resulting profile with the rest of the
         // existing profiles.
         profile_to_merge = existing_profile;
       }
     }
   }
+
+  AutofillMetrics::LogNumberOfProfilesRemovedDuringDedupe(
+      profile_guids_to_delete->size());
 }
 
 }  // namespace autofill