Remove "Show saved copy" button from error page

chrome/renderer/net/net_error_page_controller.cc

 // 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.
 
 #include "chrome/renderer/net/net_error_page_controller.h"
 
 #include "base/strings/string_piece.h"
 #include "content/public/renderer/render_frame.h"
 #include "gin/handle.h"
 #include "gin/object_template_builder.h"
@@ skipping 29 matching lines @@
 }
 
 bool NetErrorPageController::ShowSavedCopyButtonClick() {
   return ButtonClick(error_page::NetErrorHelperCore::SHOW_SAVED_COPY_BUTTON);
 }
 
 bool NetErrorPageController::ShowOfflinePagesButtonClick() {
   return ButtonClick(error_page::NetErrorHelperCore::SHOW_OFFLINE_PAGES_BUTTON);
 }
 
-bool NetErrorPageController::ShowOfflineCopyButtonClick() {
-  return ButtonClick(error_page::NetErrorHelperCore::SHOW_OFFLINE_COPY_BUTTON);
-}
-
 bool NetErrorPageController::ReloadButtonClick() {
   return ButtonClick(error_page::NetErrorHelperCore::RELOAD_BUTTON);
 }
 
 bool NetErrorPageController::DetailsButtonClick() {
   return ButtonClick(error_page::NetErrorHelperCore::MORE_BUTTON);
 }
 
 bool NetErrorPageController::TrackEasterEgg() {
   return ButtonClick(error_page::NetErrorHelperCore::EASTER_EGG);
@@ skipping 31 matching lines @@
 NetErrorPageController::~NetErrorPageController() {}
 
 gin::ObjectTemplateBuilder NetErrorPageController::GetObjectTemplateBuilder(
     v8::Isolate* isolate) {
   return gin::Wrappable<NetErrorPageController>::GetObjectTemplateBuilder(
              isolate)
       .SetMethod("showSavedCopyButtonClick",
                  &NetErrorPageController::ShowSavedCopyButtonClick)
       .SetMethod("showOfflinePagesButtonClick",
                  &NetErrorPageController::ShowOfflinePagesButtonClick)
-      .SetMethod("showOfflineCopyButtonClick",
-                 &NetErrorPageController::ShowOfflineCopyButtonClick)
       .SetMethod("reloadButtonClick",
                  &NetErrorPageController::ReloadButtonClick)
       .SetMethod("detailsButtonClick",
                  &NetErrorPageController::DetailsButtonClick)
       .SetMethod("diagnoseErrorsButtonClick",
                  &NetErrorPageController::DiagnoseErrorsButtonClick)
       .SetMethod("trackClick", &NetErrorPageController::TrackClick)
       .SetMethod("trackEasterEgg", &NetErrorPageController::TrackEasterEgg)
       .SetMethod("trackCachedCopyButtonClick",
                  &NetErrorPageController::TrackCachedCopyButtonClick);
 }