Refactor UKM interface for mojo-ification

components/ukm/ukm_entry.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/ukm_entry.h"
-
-#include "base/metrics/metrics_hashes.h"
-#include "components/metrics/proto/ukm/entry.pb.h"
-#include "components/ukm/ukm_source.h"
-
-namespace ukm {
-
-UkmEntry::UkmEntry(int32_t source_id, const char* event_name)
-    : source_id_(source_id), event_hash_(base::HashMetricName(event_name)) {}
-
-UkmEntry::~UkmEntry() {}
-
-void UkmEntry::PopulateProto(Entry* proto_entry) const {
-  DCHECK(!proto_entry->has_source_id());
-  DCHECK(!proto_entry->has_event_hash());
-
-  proto_entry->set_source_id(source_id_);
-  proto_entry->set_event_hash(event_hash_);
-  for (auto& metric : metrics_) {
-    Entry::Metric* proto_metric = proto_entry->add_metrics();
-    proto_metric->set_metric_hash(std::get<0>(metric));
-    proto_metric->set_value(std::get<1>(metric));
-  }
-}
-
-}  // namespace ukm