Implement Harmony textfield border

ui/views/examples/textfield_example.h

 // Copyright (c) 2012 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 UI_VIEWS_EXAMPLES_TEXTFIELD_EXAMPLE_H_
 #define UI_VIEWS_EXAMPLES_TEXTFIELD_EXAMPLE_H_
 
 #include <string>
 
 #include "base/macros.h"
@@ skipping 30 matching lines @@
   // ButtonListener:
   void ButtonPressed(Button* sender, const ui::Event& event) override;
 
   // Textfields for name and password.
   Textfield* name_;
   Textfield* password_;
   Textfield* read_only_;
 
   // Various buttons to control textfield.
   LabelButton* show_password_;
+  LabelButton* set_background_;
   LabelButton* clear_all_;
   LabelButton* append_;
   LabelButton* set_;
   LabelButton* set_style_;
 
   DISALLOW_COPY_AND_ASSIGN(TextfieldExample);
 };
 
 }  // namespace examples
 }  // namespace views
 
 #endif  // UI_VIEWS_EXAMPLES_TEXTFIELD_EXAMPLE_H_