Split a MetricsLogStore object out of MetricsLogManager.

components/ukm/persisted_logs_metrics_impl.cc

 // Copyright 2017 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/ukm/persisted_logs_metrics_impl.h"
 
 #include "base/metrics/histogram_macros.h"
 
 namespace ukm {
 
 PersistedLogsMetricsImpl::PersistedLogsMetricsImpl() = default;
 
 PersistedLogsMetricsImpl::~PersistedLogsMetricsImpl() = default;
 
-metrics::PersistedLogs::LogReadStatus
-PersistedLogsMetricsImpl::RecordLogReadStatus(
-    metrics::PersistedLogs::LogReadStatus status) {
+void PersistedLogsMetricsImpl::RecordLogReadStatus(
+    metrics::PersistedLogsMetrics::LogReadStatus status) {
   UMA_HISTOGRAM_ENUMERATION("UKM.PersistentLogRecall.Status", status,
-                            metrics::PersistedLogs::END_RECALL_STATUS);
-  return status;
+                            metrics::PersistedLogsMetrics::END_RECALL_STATUS);
 }
 
 void PersistedLogsMetricsImpl::RecordCompressionRatio(size_t compressed_size,
                                                       size_t original_size) {
   UMA_HISTOGRAM_PERCENTAGE(
       "UKM.ProtoCompressionRatio",
       static_cast<int>(100 * compressed_size / original_size));
 }
 
 void PersistedLogsMetricsImpl::RecordDroppedLogSize(size_t size) {
   UMA_HISTOGRAM_COUNTS_1M("UKM.UnsentLogs.DroppedSize", static_cast<int>(size));
 }
 
 void PersistedLogsMetricsImpl::RecordDroppedLogsNum(int dropped_logs_num) {
   UMA_HISTOGRAM_COUNTS_10000("UKM.UnsentLogs.NumDropped", dropped_logs_num);
 }
 
 }  // namespace ukm