libchrome: Several upstreamable fixes from libchrome

base/metrics/sparse_histogram.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/sparse_histogram.h"
 
 #include <utility>
 
 #include "base/memory/ptr_util.h"
 #include "base/metrics/metrics_hashes.h"
@@ skipping 75 matching lines @@
 
 uint64_t SparseHistogram::name_hash() const {
   return samples_->id();
 }
 
 HistogramType SparseHistogram::GetHistogramType() const {
   return SPARSE_HISTOGRAM;
 }
 
 bool SparseHistogram::HasConstructionArguments(
-    Sample expected_minimum,
-    Sample expected_maximum,
-    uint32_t expected_bucket_count) const {
+    Sample /* expected_minimum */,
+    Sample /* expected_maximum */,
+    uint32_t /* expected_bucket_count */) const {
   // SparseHistogram never has min/max/bucket_count limit.
   return false;
 }
 
 void SparseHistogram::Add(Sample value) {
   AddCount(value, 1);
 }
 
 void SparseHistogram::AddCount(Sample value, int count) {
   if (count <= 0) {
@@ skipping 98 matching lines @@
     DLOG(ERROR) << "Pickle error decoding Histogram: " << histogram_name;
     return NULL;
   }
 
   DCHECK(flags & HistogramBase::kIPCSerializationSourceFlag);
   flags &= ~HistogramBase::kIPCSerializationSourceFlag;
 
   return SparseHistogram::FactoryGet(histogram_name, flags);
 }
 
-void SparseHistogram::GetParameters(DictionaryValue* params) const {
+void SparseHistogram::GetParameters(DictionaryValue* /* params */) const {
   // TODO(kaiwang): Implement. (See HistogramBase::WriteJSON.)
 }
 
-void SparseHistogram::GetCountAndBucketData(Count* count,
-                                            int64_t* sum,
-                                            ListValue* buckets) const {
+void SparseHistogram::GetCountAndBucketData(Count* /* count */,
+                                            int64_t* /* sum */,
+                                            ListValue* /* buckets */) const {
   // TODO(kaiwang): Implement. (See HistogramBase::WriteJSON.)
 }
 
 void SparseHistogram::WriteAsciiImpl(bool graph_it,
                                      const std::string& newline,
                                      std::string* output) const {
   // Get a local copy of the data so we are consistent.
   std::unique_ptr<HistogramSamples> snapshot = SnapshotSamples();
   Count total_count = snapshot->TotalCount();
   double scaled_total_count = total_count / 100.0;
@@ skipping 47 matching lines @@
                                        std::string* output) const {
   StringAppendF(output,
                 "Histogram: %s recorded %d samples",
                 histogram_name().c_str(),
                 total_count);
   if (flags() & ~kHexRangePrintingFlag)
     StringAppendF(output, " (flags = 0x%x)", flags() & ~kHexRangePrintingFlag);
 }
 
 }  // namespace base