Add SampleMap and use it in SparseHistogram

base/metrics/sample_vector.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/sample_vector.h"
 
 #include "base/logging.h"
 #include "base/metrics/bucket_ranges.h"
 
 using std::vector;
@@ skipping 35 matching lines @@
   DCHECK(bucket_index >= 0 && bucket_index < counts_.size());
   return counts_[bucket_index];
 }
 
 scoped_ptr<SampleCountIterator> SampleVector::Iterator() const {
   return scoped_ptr<SampleCountIterator>(
       new SampleVectorIterator(&counts_, bucket_ranges_));
 }
 
 bool SampleVector::AddSubtractImpl(SampleCountIterator* iter,
-                                   HistogramSamples::Instruction instruction) {
+                                   HistogramSamples::Operator op) {
   HistogramBase::Sample min;
   HistogramBase::Sample max;
   HistogramBase::Count count;
 
   // Go through the iterator and add the counts into correct bucket.
   size_t index = 0;
   while (index < counts_.size() && !iter->Done()) {
     iter->Get(&min, &max, &count);
     if (min == bucket_ranges_->range(index) &&
         max == bucket_ranges_->range(index + 1)) {
       // Sample matches this bucket!
-      counts_[index] +=
-          (instruction ==  HistogramSamples::ADD) ? count : -count;
+      counts_[index] += (op ==  HistogramSamples::ADD) ? count : -count;
       iter->Next();
     } else if (min > bucket_ranges_->range(index)) {
       // Sample is larger than current bucket range. Try next.
       index++;
     } else {
       // Sample is smaller than current bucket range. We scan buckets from
       // smallest to largest, so the sample value must be invalid.
       return false;
     }
   }
@@ skipping 30 matching lines @@
 
 SampleVectorIterator::SampleVectorIterator(const vector<Count>* counts,
                                            const BucketRanges* bucket_ranges)
     : counts_(counts),
       bucket_ranges_(bucket_ranges),
       index_(0) {
   CHECK_GT(bucket_ranges_->size(), counts_->size());
   SkipEmptyBuckets();
 }
 
+SampleVectorIterator::~SampleVectorIterator() {}
+
 bool SampleVectorIterator::Done() const {
   return index_ >= counts_->size();
 }
 
 void SampleVectorIterator::Next() {
   DCHECK(!Done());
   index_++;
   SkipEmptyBuckets();
 }
 
@@ skipping 21 matching lines @@
     return;
 
   while (index_ < counts_->size()) {
     if ((*counts_)[index_] != 0)
       return;
     index_++;
   }
 }
 
 }  // namespace base