components: Change auto to not deduce raw pointers.

components/ntp_snippets/ntp_snippets_fetcher.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/ntp_snippets_fetcher.h"
 
 #include <stdlib.h>
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
@@ skipping 243 matching lines @@
 NTPSnippetsFetcher::RequestParams::~RequestParams() = default;
 
 std::string NTPSnippetsFetcher::RequestParams::BuildRequest() {
   auto request = base::MakeUnique<base::DictionaryValue>();
   if (fetch_api == CHROME_READER_API) {
     auto content_params = base::MakeUnique<base::DictionaryValue>();
     content_params->SetBoolean("only_return_personalized_results",
                                only_return_personalized_results);
 
     auto content_restricts = base::MakeUnique<base::ListValue>();
-    for (const auto& metadata : {"TITLE", "SNIPPET", "THUMBNAIL"}) {
+    for (const auto* metadata : {"TITLE", "SNIPPET", "THUMBNAIL"}) {
       auto entry = base::MakeUnique<base::DictionaryValue>();
       entry->SetString("type", "METADATA");
       entry->SetString("value", metadata);
       content_restricts->Append(std::move(entry));
     }
 
     auto content_selectors = base::MakeUnique<base::ListValue>();
     for (const auto& host : host_restricts) {
       auto entry = base::MakeUnique<base::DictionaryValue>();
       entry->SetString("type", "HOST_RESTRICT");
@@ skipping 244 matching lines @@
                       tick_clock_->NowTicks() - fetch_start_time_);
   UMA_HISTOGRAM_ENUMERATION("NewTabPage.Snippets.FetchResult",
                             static_cast<int>(result),
                             static_cast<int>(FetchResult::RESULT_MAX));
 
   if (!snippets_available_callback_.is_null())
     snippets_available_callback_.Run(std::move(snippets));
 }
 
 }  // namespace ntp_snippets