Add UMA Histogram Manager to Cronet.

components/metrics/metrics_log.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/metrics_log.h"
 
 #include <algorithm>
 #include <string>
 #include <vector>
 
 #include "base/base64.h"
 #include "base/basictypes.h"
 #include "base/build_time.h"
 #include "base/cpu.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/histogram_samples.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/pref_service.h"
 #include "base/sha1.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/sys_info.h"
 #include "base/time/time.h"
+#include "components/metrics/histogram_encoder.h"
 #include "components/metrics/metrics_hashes.h"
 #include "components/metrics/metrics_pref_names.h"
 #include "components/metrics/metrics_provider.h"
 #include "components/metrics/metrics_service_client.h"
 #include "components/metrics/proto/histogram_event.pb.h"
 #include "components/metrics/proto/system_profile.pb.h"
 #include "components/metrics/proto/user_action_event.pb.h"
 #include "components/variations/active_field_trials.h"
 
 #if defined(OS_ANDROID)
@@ skipping 135 matching lines @@
   DCHECK(!closed_);
 
   UserActionEventProto* user_action = uma_proto_.add_user_action_event();
   user_action->set_name_hash(Hash(key));
   user_action->set_time(GetCurrentTime());
 }
 
 void MetricsLog::RecordHistogramDelta(const std::string& histogram_name,
                                       const base::HistogramSamples& snapshot) {
   DCHECK(!closed_);
-  DCHECK_NE(0, snapshot.TotalCount());
-
-  // 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(Hash(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();
-    }
-  }
+  EncodeHistogramDelta(histogram_name, snapshot, &uma_proto_);
 }
 
 void MetricsLog::RecordStabilityMetrics(
     const std::vector<MetricsProvider*>& metrics_providers,
     base::TimeDelta incremental_uptime,
     base::TimeDelta uptime) {
   DCHECK(!closed_);
   DCHECK(HasEnvironment());
   DCHECK(!HasStabilityMetrics());
 
@@ skipping 206 matching lines @@
   DCHECK(!closed_);
   closed_ = true;
 }
 
 void MetricsLog::GetEncodedLog(std::string* encoded_log) {
   DCHECK(closed_);
   uma_proto_.SerializeToString(encoded_log);
 }
 
 }  // namespace metrics