Refactor MdFocusRing to make it easier to reuse on other controls.

ui/views/controls/focusable_border.h

 // Copyright (c) 2011 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_CONTROLS_FOCUSABLE_BORDER_H_
 #define UI_VIEWS_CONTROLS_FOCUSABLE_BORDER_H_
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "ui/views/border.h"
 #include "ui/views/view.h"
 
 namespace gfx {
 class Canvas;
 class Insets;
 }
 
 namespace views {
 
 // A Border class to draw a focused border around a field (e.g textfield).
 class VIEWS_EXPORT FocusableBorder : public Border {
  public:
-  static constexpr float kCornerRadiusDp = 1.5f;
+  static constexpr float kCornerRadiusDp = 2.f;
 
   FocusableBorder();
   ~FocusableBorder() override;
 
   // Sets the insets of the border.
   void SetInsets(int top, int left, int bottom, int right);
 
   // Sets the color of this border.
   void SetColor(SkColor color);
   // Reverts the color of this border to the system default.
@@ skipping 16 matching lines @@
   // Whether the system border color should be used. True unless SetColor has
   // been called.
   bool use_default_color_;
 
   DISALLOW_COPY_AND_ASSIGN(FocusableBorder);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_FOCUSABLE_BORDER_H_