Remove unnecessary Border subclasses where we can achieve the same functionality

chrome/browser/ui/views/infobars/infobar_button_border.cc

-// 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.
-
-#include "chrome/browser/ui/views/infobars/infobar_button_border.h"
-
-#include "chrome/browser/defaults.h"
-#include "grit/theme_resources.h"
-#include "ui/views/painter.h"
-
-namespace {
-
-const int kNormalImageSet[] = IMAGE_GRID(IDR_INFOBARBUTTON_NORMAL);
-const int kHotImageSet[] = IMAGE_GRID(IDR_INFOBARBUTTON_HOVER);
-const int kPushedImageSet[] = IMAGE_GRID(IDR_INFOBARBUTTON_PRESSED);
-
-}  // namespace
-
-InfoBarButtonBorder::InfoBarButtonBorder() {
-  gfx::Insets insets = GetInsets();
-  SetInsets(gfx::Insets(browser_defaults::kInfoBarBorderPaddingVertical,
-                        insets.left(),
-                        browser_defaults::kInfoBarBorderPaddingVertical,
-                        insets.right()));
-
-  set_normal_painter(views::Painter::CreateImageGridPainter(kNormalImageSet));
-  set_hot_painter(views::Painter::CreateImageGridPainter(kHotImageSet));
-  set_pushed_painter(views::Painter::CreateImageGridPainter(kPushedImageSet));
-}
-
-InfoBarButtonBorder::~InfoBarButtonBorder() {
-}