NTPSnippets: User locale was not set when user isn't signed in.

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 436 matching lines @@
   GURL url(base::StringPrintf(kSnippetsServerNonAuthorizedFormat,
                               fetch_url_.spec().c_str(), key.c_str()));
 
   RequestParams params;
   params.fetch_api = fetch_api_;
   params.host_restricts =
       UsesHostRestrictions() ? hosts_ : std::set<std::string>();
   params.excluded_ids = excluded_ids_;
   params.count_to_fetch = count_to_fetch_;
   params.interactive_request = interactive_request_;
+  params.user_locale = locale_;
   FetchSnippetsImpl(url, std::string(), params.BuildRequest());
 }
 
 void NTPSnippetsFetcher::FetchSnippetsAuthenticated(
     const std::string& account_id,
     const std::string& oauth_access_token) {
   RequestParams params;
   params.fetch_api = fetch_api_;
   params.obfuscated_gaia_id = account_id;
   params.only_return_personalized_results =
@@ skipping 198 matching lines @@
   UMA_HISTOGRAM_ENUMERATION("NewTabPage.Snippets.FetchResult",
                             static_cast<int>(result),
                             static_cast<int>(FetchResult::RESULT_MAX));
 
   DVLOG(1) << "Fetch finished: " << last_status_;
   if (!snippets_available_callback_.is_null())
     snippets_available_callback_.Run(std::move(snippets));
 }
 
 }  // namespace ntp_snippets