Upstream (most of) ios/web/public

ios/web/public/user_metrics.h

Index: ios/web/public/user_metrics.h
diff --git a/ios/web/public/user_metrics.h b/ios/web/public/user_metrics.h
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index 0000000000000000000000000000000000000000..2f354edecfd4542f7da87266660de9a9b407135a
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+// Copyright 2014 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 IOS_WEB_PUBLIC_USER_METRICS_H_
+#define IOS_WEB_PUBLIC_USER_METRICS_H_
+
+#include <string>
+
+#include "base/callback.h"
+
+namespace base {
+struct UserMetricsAction;
+}  // namespace base
+
+namespace web {
+
+// Wrappers around functions defined in base/metrics/user_metrics.h, refer to
+// that header for full documentation. These wrappers can be called from any
+// thread (they will post back to the UI thread to do the recording).
+
+void RecordAction(const base::UserMetricsAction& action);
+void RecordComputedAction(const std::string& action);
+
+}  // namespace web
+
+#endif  // IOS_WEB_PUBLIC_USER_METRICS_H_