[translate] Add translate ranker model loader.

chrome/browser/translate/translate_ranker_metrics_provider.cc

+// Copyright 2016 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 "chrome/browser/translate/translate_ranker_metrics_provider.h"
+
+#include "chrome/browser/profiles/profile_manager.h"
+#include "chrome/browser/translate/translate_ranker_factory.h"
+#include "components/metrics/proto/chrome_user_metrics_extension.pb.h"
+#include "components/metrics/proto/translate_event.pb.h"
+#include "components/translate/core/browser/translate_ranker.h"
+
+namespace translate {
+
+void TranslateRankerMetricsProvider::ProvideGeneralMetrics(
+    metrics::ChromeUserMetricsExtension* uma_proto) {
+  for (auto* profile : ProfileManager::GetLastOpenedProfiles()) {
+    TranslateRanker* ranker =
+        TranslateRankerFactory::GetInstance()->GetForBrowserContext(profile);
+    if (!ranker)
+      return;
+
+    std::vector<metrics::TranslateEventProto> translate_events;
+    ranker->FlushTranslateEvents(&translate_events);
+
+    for (auto& event : translate_events) {
+      uma_proto->add_translate_event()->Swap(&event);
+    }
+  }
+}
+
+}  // namespace translate