Avoid double initializing reporting_service_

components/metrics/reporting_service.cc

 // Copyright 2017 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.
 
 // ReportingService handles uploading serialized logs to a server.
 
 #include "components/metrics/reporting_service.h"
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 25 matching lines @@
   DCHECK(client_);
   DCHECK(local_state);
 }
 
 ReportingService::~ReportingService() {
   DisableReporting();
 }
 
 void ReportingService::Initialize() {
   DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(!upload_scheduler_);
   log_store()->LoadPersistedUnsentLogs();
   base::Closure send_next_log_callback = base::Bind(
       &ReportingService::SendNextLog, self_ptr_factory_.GetWeakPtr());
   upload_scheduler_.reset(new MetricsUploadScheduler(send_next_log_callback));
 }
 
 void ReportingService::Start() {
   DCHECK(thread_checker_.CalledOnValidThread());
   if (reporting_active_)
     upload_scheduler_->Start();
@@ skipping 132 matching lines @@
   // don't consider that a sign that the server is in trouble.
   bool server_is_healthy = upload_succeeded || response_code == 400;
   if (!log_store()->has_unsent_logs()) {
     DVLOG(1) << "Stopping upload_scheduler_.";
     upload_scheduler_->Stop();
   }
   upload_scheduler_->UploadFinished(server_is_healthy);
 }
 
 }  // namespace metrics