libchrome: Several upstreamable fixes from libchrome

base/metrics/statistics_recorder.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 "base/metrics/statistics_recorder.h"
 
 #include <memory>
 
 #include "base/at_exit.h"
 #include "base/debug/leak_annotations.h"
@@ skipping 485 matching lines @@
     callbacks_deleter.reset(callbacks_);
     ranges_deleter.reset(ranges_);
     histograms_ = NULL;
     callbacks_ = NULL;
     ranges_ = NULL;
   }
   // We are going to leak the histograms and the ranges.
 }
 
 // static
-void StatisticsRecorder::DumpHistogramsToVlog(void* instance) {
+void StatisticsRecorder::DumpHistogramsToVlog(void* /* instance */) {
   std::string output;
   StatisticsRecorder::WriteGraph(std::string(), &output);
   VLOG(1) << output;
 }
 
 
 // static
 StatisticsRecorder::HistogramMap* StatisticsRecorder::histograms_ = NULL;
 // static
 StatisticsRecorder::CallbackMap* StatisticsRecorder::callbacks_ = NULL;
 // static
 StatisticsRecorder::RangesMap* StatisticsRecorder::ranges_ = NULL;
 // static
 base::Lock* StatisticsRecorder::lock_ = NULL;
 
 }  // namespace base