Downloading the json file from ChromeReader is tried several times when ERR_NETW…

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 "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/path_service.h"
 #include "base/strings/string_util.h"
@@ skipping 103 matching lines @@
                     base::StringPrintf(kAuthorizationRequestHeaderFormat,
                                        access_token.c_str()));
   headers.SetHeader("Content-Type", "application/json; charset=UTF-8");
   url_fetcher_->SetExtraRequestHeaders(headers.ToString());
   std::string host_restricts;
   for (const std::string& host : hosts_)
     host_restricts += base::StringPrintf(kHostRestrictFormat, host.c_str());
   url_fetcher_->SetUploadData("application/json",
                               base::StringPrintf(kRequestParameterFormat,
                                                  host_restricts.c_str()));
+
+  // Fetchers are sometimes cancelled because a network change was detected.
+  url_fetcher_->SetAutomaticallyRetryOnNetworkChanges(3);
+  // Try to make fetching the files bit more robust even with poor connection.
+  url_fetcher_->SetMaxRetriesOn5xx(3);
   url_fetcher_->Start();
 }
 
 void NTPSnippetsFetcher::OnGetTokenFailure(
     const OAuth2TokenService::Request* request,
     const GoogleServiceAuthError& error) {
   oauth_request_.reset();
   DLOG(ERROR) << "Unable to get token: " << error.ToString();
 }
 
@@ skipping 26 matching lines @@
   }
 
   std::string response;
   bool stores_result_to_string = source->GetResponseAsString(&response);
   DCHECK(stores_result_to_string);
 
   callback_list_.Notify(response);
 }
 
 }  // namespace ntp_snippets