[UMA, Cleanup] Remove an unneeded timing-related histogram.

chrome/browser/chromeos/external_metrics.cc

 // Copyright (c) 2012 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 "chrome/browser/chromeos/external_metrics.h"
 
 #include <map>
 #include <string>
 
 #include "base/bind.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/sparse_histogram.h"
 #include "base/metrics/statistics_recorder.h"
-#include "base/timer/elapsed_timer.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/metrics/chromeos_metrics_provider.h"
 #include "components/metrics/metrics_service.h"
 #include "components/metrics/serialization/metric_sample.h"
 #include "components/metrics/serialization/serialization_utils.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/user_metrics.h"
 
 using base::UserMetricsAction;
 using content::BrowserThread;
@@ skipping 133 matching lines @@
       case metrics::MetricSample::SPARSE_HISTOGRAM:
         RecordSparseHistogram(sample);
         break;
     }
   }
 
   return samples.size();
 }
 
 void ExternalMetrics::CollectEventsAndReschedule() {
-  base::ElapsedTimer timer;
   CollectEvents();
-  UMA_HISTOGRAM_TIMES("UMA.CollectExternalEventsTime", timer.Elapsed());
   ScheduleCollector();
 }
 
 void ExternalMetrics::ScheduleCollector() {
   bool result = BrowserThread::GetBlockingPool()->PostDelayedWorkerTask(
       FROM_HERE,
       base::Bind(&chromeos::ExternalMetrics::CollectEventsAndReschedule, this),
       base::TimeDelta::FromSeconds(kExternalMetricsCollectionIntervalSeconds));
   DCHECK(result);
 }
 
 }  // namespace chromeos