Add factory class for CertificateReportingService and a new metrics provider.

chrome/browser/safe_browsing/certificate_reporting_metrics_provider.h

+// 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.
+
+#ifndef CHROME_BROWSER_SAFE_BROWSING_CERTIFICATE_REPORTING_METRICS_PROVIDER_H_
+#define CHROME_BROWSER_SAFE_BROWSING_CERTIFICATE_REPORTING_METRICS_PROVIDER_H_
+
+#include "base/macros.h"
+#include "components/metrics/metrics_provider.h"
+
+// When user metrics are about to be uploaded,
+// CertificateReportingMetricsProvider looks up the CertificateReportingService
+// for the current profile and tells it to record its metrics before the upload
+// occurs.
+class CertificateReportingMetricsProvider : public metrics::MetricsProvider {
+ public:
+  CertificateReportingMetricsProvider();
+  ~CertificateReportingMetricsProvider() override;
+
+  // metrics:MetricsProvider:
+  void ProvideGeneralMetrics(
+      metrics::ChromeUserMetricsExtension* unused) override;
+};
+
+#endif  // CHROME_BROWSER_SAFE_BROWSING_CERTIFICATE_REPORTING_METRICS_PROVIDER_H_