[Autofill] Add upstreaming UKM

components/autofill/core/browser/autofill_ukm.h

+// 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.
+
+#ifndef COMPONENTS_AUTOFILL_CORE_BROWSER_AUTOFILL_UKM_H_
+#define COMPONENTS_AUTOFILL_CORE_BROWSER_AUTOFILL_UKM_H_
+
+#include "base/macros.h"
+#include "components/autofill/core/browser/autofill_metrics.h"
+
+class GURL;
+
+namespace ukm {
+class UkmService;
+}  // namespace ukm
+
+namespace autofill {
+
+// A class to log Autofill related Url Keyed Metrics.
+class AutofillUkm {

[Mathieu, 2017/03/09 18:40:49]

I don't think we need the class, right? LogUkm could just sit in AutofillMetrics
as a static.

[sebsg, 2017/03/09 19:57:04]

Done.

+ public:
+  // Logs the the |ukm| with the specified |url| and the specified |metrics|.
+  // Returns whether the ukm was sucessfully logged.
+  static bool LogUkm(ukm::UkmService* ukm_service,
+                     const GURL& url,
+                     const std::string& ukm,
+                     const std::map<std::string, int>& metrics);
+
+ private:
+  AutofillUkm(){};
+};
+
+}  // namespace autofill
+
+#endif  // COMPONENTS_AUTOFILL_CORE_BROWSER_AUTOFILL_UKM_H_