[NTP Snippets] Cleanups from clang-tidy

components/ntp_snippets/offline_pages/offline_page_proxy.cc

 // Copyright 2016 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 "components/ntp_snippets/offline_pages/offline_page_proxy.h"
 
 #include "base/bind.h"
 
 using offline_pages::MultipleOfflinePageItemResult;
 using offline_pages::MultipleOfflinePageItemCallback;
 using offline_pages::OfflinePageModel;
-using offline_pages::OfflinePageItem;
 
 namespace ntp_snippets {
 
 OfflinePageProxy::OfflinePageProxy(OfflinePageModel* offline_page_model)
     : offline_page_model_(offline_page_model), weak_ptr_factory_(this) {
   offline_page_model_->AddObserver(this);
 }
 
 void OfflinePageProxy::GetAllPages(
     const MultipleOfflinePageItemCallback& callback) {
@@ skipping 35 matching lines @@
   offline_page_model_->GetAllPages(base::Bind(
       &OfflinePageProxy::OnOfflinePagesLoaded, weak_ptr_factory_.GetWeakPtr()));
 }
 
 void OfflinePageProxy::OnOfflinePagesLoaded(
     const MultipleOfflinePageItemResult& result) {
   FOR_EACH_OBSERVER(Observer, observers_, OfflinePageModelChanged(result));
 }
 
 }  // namespace ntp_snippets