[NTP Snippets] Another round of clang-tidy cleanups

components/ntp_snippets/remote/request_throttler.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/remote/request_throttler.h"
 
 #include <climits>
 #include <set>
 #include <vector>
 
@@ skipping 135 matching lines @@
   } else {
     histogram_request_status_->Add(
         static_cast<int>(available ? RequestStatus::BACKGROUND_QUOTA_GRANTED
                                    : RequestStatus::BACKGROUND_QUOTA_EXCEEDED));
   }
   return available;
 }
 
 void RequestThrottler::ResetCounterIfDayChanged() {
   // Get the date, "concatenated" into an int in "YYYYMMDD" format.
-  base::Time::Exploded now_exploded;
+  base::Time::Exploded now_exploded{};
   base::Time::Now().LocalExplode(&now_exploded);
   int now_day = 10000 * now_exploded.year + 100 * now_exploded.month +
                 now_exploded.day_of_month;
 
   if (!HasDay()) {
     // The counter is used for the first time in this profile.
     SetDay(now_day);
   } else if (now_day != GetDay()) {
     // Day has changed - report the number of requests from the previous day.
     histogram_per_day_background_->Add(GetCount(/*interactive_request=*/false));
@@ skipping 34 matching lines @@
 
 void RequestThrottler::SetDay(int day) {
   pref_service_->SetInteger(type_info_.day_pref, day);
 }
 
 bool RequestThrottler::HasDay() const {
   return pref_service_->HasPrefPath(type_info_.day_pref);
 }
 
 }  // namespace ntp_snippets