[Autofill] Tweak credit card signin promo visually.

chrome/browser/ui/autofill/autofill_popup_controller_impl.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 CHROME_BROWSER_UI_AUTOFILL_AUTOFILL_POPUP_CONTROLLER_IMPL_H_
 #define CHROME_BROWSER_UI_AUTOFILL_AUTOFILL_POPUP_CONTROLLER_IMPL_H_
 
 #include <stddef.h>
 
 #include "base/gtest_prod_util.h"
@@ skipping 83 matching lines @@
   const base::string16& GetElidedValueAt(size_t row) const override;
   const base::string16& GetElidedLabelAt(size_t row) const override;
   bool GetRemovalConfirmationText(int list_index,
                                   base::string16* title,
                                   base::string16* body) override;
   bool RemoveSuggestion(int list_index) override;
 #if !defined(OS_ANDROID)
   const gfx::FontList& GetValueFontListForRow(size_t index) const override;
   const gfx::FontList& GetLabelFontList() const override;
 #endif
+  SkColor GetBackgroundColorForRow(int index) const override;
   int selected_line() const override;
   const AutofillPopupLayoutModel& layout_model() const override;
 
   content::WebContents* web_contents();
 
   // Change which line is currently selected by the user.
   void SetSelectedLine(int selected_line);
 
   // Increase the selected line by 1, properly handling wrapping.
   void SelectNextLine();
@@ skipping 71 matching lines @@
   // The line that is currently selected by the user.
   // |kNoSelection| indicates that no line is currently selected.
   int selected_line_;
 
   base::WeakPtrFactory<AutofillPopupControllerImpl> weak_ptr_factory_;
 };
 
 }  // namespace autofill
 
 #endif  // CHROME_BROWSER_UI_AUTOFILL_AUTOFILL_POPUP_CONTROLLER_IMPL_H_