Remove unused feedback class in dom distiller component

components/dom_distiller/core/viewer.h

 // Copyright 2014 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 COMPONENTS_DOM_DISTILLER_CORE_VIEWER_H_
 #define COMPONENTS_DOM_DISTILLER_CORE_VIEWER_H_
 
 #include <memory>
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "base/strings/string16.h"
 #include "components/dom_distiller/core/distilled_page_prefs.h"
 #include "ui/gfx/geometry/size.h"
 
 namespace dom_distiller {
 
 class DistilledArticleProto;
 class DistilledPageProto;
 class DomDistillerServiceInterface;
 class ViewerHandle;
 class ViewRequestDelegate;
 
 namespace viewer {
 
-// Returns the JavaScript to show the feedback footer for a distilled page.
-const std::string GetShowFeedbackFormJs();
-
 // Returns an HTML template page based on the given |page_proto| which provides
 // basic information about the page (i.e. title, text direction, etc.). This is
 // supposed to be displayed to the end user. The returned HTML should be
 // considered unsafe, so callers must ensure rendering it does not compromise
 // Chrome.
 const std::string GetUnsafeArticleTemplateHtml(
     const std::string original_url,
     const DistilledPagePrefs::Theme theme,
     const DistilledPagePrefs::FontFamily font_family);
 
@@ skipping 54 matching lines @@
 const std::string GetDistilledPageThemeJs(DistilledPagePrefs::Theme theme);
 
 // Returns JavaScript corresponding to setting the font scaling.
 const std::string GetDistilledPageFontScalingJs(float scaling);
 
 }  // namespace viewer
 
 }  // namespace dom_distiller
 
 #endif  // COMPONENTS_DOM_DISTILLER_CORE_VIEWER_H_