Revert "Add UMA Histogram Manager to Cronet."

components/metrics/histogram_encoder.cc

-// Copyright 2014 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 "components/metrics/histogram_encoder.h"
-
-#include <string>
-
-#include "base/basictypes.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/metrics/histogram.h"
-#include "base/metrics/histogram_samples.h"
-#include "components/metrics/metrics_hashes.h"
-
-using base::SampleCountIterator;
-
-namespace metrics {
-
-void EncodeHistogramDelta(const std::string& histogram_name,
-                          const base::HistogramSamples& snapshot,
-                          ChromeUserMetricsExtension* uma_proto) {
-  DCHECK_NE(0, snapshot.TotalCount());
-  DCHECK(uma_proto);
-
-  // We will ignore the MAX_INT/infinite value in the last element of range[].
-
-  HistogramEventProto* histogram_proto = uma_proto->add_histogram_event();
-  histogram_proto->set_name_hash(HashMetricName(histogram_name));
-  histogram_proto->set_sum(snapshot.sum());
-
-  for (scoped_ptr<SampleCountIterator> it = snapshot.Iterator(); !it->Done();
-       it->Next()) {
-    base::Histogram::Sample min;
-    base::Histogram::Sample max;
-    base::Histogram::Count count;
-    it->Get(&min, &max, &count);
-    HistogramEventProto::Bucket* bucket = histogram_proto->add_bucket();
-    bucket->set_min(min);
-    bucket->set_max(max);
-    bucket->set_count(count);
-  }
-
-  // Omit fields to save space (see rules in histogram_event.proto comments).
-  for (int i = 0; i < histogram_proto->bucket_size(); ++i) {
-    HistogramEventProto::Bucket* bucket = histogram_proto->mutable_bucket(i);
-    if (i + 1 < histogram_proto->bucket_size() &&
-        bucket->max() == histogram_proto->bucket(i + 1).min()) {
-      bucket->clear_max();
-    } else if (bucket->max() == bucket->min() + 1) {
-      bucket->clear_min();
-    }
-  }
-}
-
-}  // namespace metrics