[Reland] Refactoring of SBER preference usage

components/safe_browsing_db/safe_browsing_prefs.cc

+// Copyright (c) 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 "base/metrics/histogram_macros.h"
+#include "components/prefs/pref_service.h"
+#include "components/safe_browsing_db/safe_browsing_prefs.h"
+
+namespace prefs {
+
+// Boolean that tell us whether Safe Browsing extended reporting is enabled.
+const char kSafeBrowsingExtendedReportingEnabled[] =
+    "safebrowsing.extended_reporting_enabled";
+
+}  // namespace prefs
+
+namespace safe_browsing {
+
+const char* GetExtendedReportingPrefName() {
+  return prefs::kSafeBrowsingExtendedReportingEnabled;
+}
+
+bool IsExtendedReportingEnabled(const PrefService& prefs) {
+  return prefs.GetBoolean(GetExtendedReportingPrefName());
+}
+
+void RecordExtendedReportingMetrics(const PrefService& prefs) {
+  UMA_HISTOGRAM_BOOLEAN("SafeBrowsing.Pref.Extended",
+                        IsExtendedReportingEnabled(prefs));
+}
+
+}  // namespace safe_browsing