UMA histogram of user action on multi-account password update bubble.

chrome/browser/ui/views/passwords/credentials_selection_view.h

Index: chrome/browser/ui/views/passwords/credentials_selection_view.h
diff --git a/chrome/browser/ui/views/passwords/credentials_selection_view.h b/chrome/browser/ui/views/passwords/credentials_selection_view.h
index 4c5d4bfe08c167e4542273e29999f56657ce0691..c20beedb36c9faa5590c6a155a6fd32917a45637 100644
--- a/chrome/browser/ui/views/passwords/credentials_selection_view.h
+++ b/chrome/browser/ui/views/passwords/credentials_selection_view.h
@@ -23,12 +23,23 @@ class CredentialsSelectionView : public views::View {
       ManagePasswordsBubbleModel* manage_passwords_bubble_model,
       const std::vector<const autofill::PasswordForm*>& password_forms,
       const base::string16& best_matched_username);
+  ~CredentialsSelectionView() override;
 
+  // This methods also reports a user action.
   const autofill::PasswordForm* GetSelectedCredentials();
 
  private:
+  views::Combobox* GenerateUsernameCombobox(
+      const std::vector<const autofill::PasswordForm*>& forms,
+      const base::string16& best_matched_username);
+  void ReportUserActionOnce(bool was_update_rejected, int selected_index);
+
   const std::vector<const autofill::PasswordForm*>& password_forms_;
   views::Combobox* combobox_;
+  int default_index_;
+  bool is_default_best_match_;
+  bool is_default_preferred_;
+  bool action_reported_;
 
   DISALLOW_COPY_AND_ASSIGN(CredentialsSelectionView);
 };