[Payments] Have expiration date be on the same line in CC editor

chrome/browser/ui/views/payments/validating_combobox.h

 // Copyright 2017 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_PAYMENTS_VALIDATING_COMBOBOX_H_
 #define CHROME_BROWSER_UI_VIEWS_PAYMENTS_VALIDATING_COMBOBOX_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 22 matching lines @@
 
   // ui::ComboboxModelObserver:
   void OnComboboxModelChanged(ui::ComboboxModel* model) override;
 
  private:
   // Will call to the ValidationDelegate to validate the contents of the
   // combobox.
   void Validate();
 
   std::unique_ptr<ValidationDelegate> delegate_;
-  bool was_blurred_ = false;
   bool being_removed_ = false;
 
   DISALLOW_COPY_AND_ASSIGN(ValidatingCombobox);
 };
 
 }  // namespace payments
 
 #endif  // CHROME_BROWSER_UI_VIEWS_PAYMENTS_VALIDATING_COMBOBOX_H_