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

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

 // Copyright 2015 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 CHROME_BROWSER_UI_VIEWS_PASSWORDS_CREDENTIALS_SELECTION_VIEW_H_
 #define CHROME_BROWSER_UI_VIEWS_PASSWORDS_CREDENTIALS_SELECTION_VIEW_H_
 
 #include <vector>
 
 #include "base/macros.h"
 #include "components/autofill/core/common/password_form.h"
 #include "ui/views/view.h"
 
 namespace views {
 class Combobox;
 }
 
 class ManagePasswordsBubbleModel;
 
 // A view where the user can select a credential.
 class CredentialsSelectionView : public views::View {
  public:
   CredentialsSelectionView(
       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);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_PASSWORDS_CREDENTIALS_SELECTION_VIEW_H_