Adding DRP specfic UMA for FirstContentfulPaint

chrome/browser/renderer_host/chrome_navigation_data.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_RENDERER_HOST_CHROME_NAVIGATION_DATA_H_
+#define CHROME_BROWSER_RENDERER_HOST_CHROME_NAVIGATION_DATA_H_
+
+#include <memory>
+
+#include "base/macros.h"
+#include "content/public/browser/navigation_data.h"
+
+namespace data_reduction_proxy {
+class DataReductionProxyData;
+}
+
+class ChromeNavigationData : public content::NavigationData {
+ public:
+  ChromeNavigationData();
+  ~ChromeNavigationData() override;
+
+  // Creates a new ChromeNavigationData that is a deep copy of the original,
+  // which could be used cross-thread.
+  // |data_reduction_proxy_data_| is deep copied.
+  std::unique_ptr<content::NavigationData> Clone() const override;
+
+  // Takes ownership of |data_reduction_proxy_data|.
+  void SetDataReductionProxyData(
+      std::unique_ptr<data_reduction_proxy::DataReductionProxyData>
+          data_reduction_proxy_data) {
+    data_reduction_proxy_data_ = std::move(data_reduction_proxy_data);
+  }
+
+  data_reduction_proxy::DataReductionProxyData* GetDataReductionProxyData() {
+    return data_reduction_proxy_data_.get();
+  }
+
+ private:
+  // Manages the lifetime of optionally passed in DataReductionProxy

[bengr, 2016/04/29 21:14:20]

nit: optionally passed in -> optional

[RyanSturm, 2016/05/02 19:52:19]

Done.

+  // information.
+  std::unique_ptr<data_reduction_proxy::DataReductionProxyData>
+      data_reduction_proxy_data_;
+
+  DISALLOW_COPY_AND_ASSIGN(ChromeNavigationData);
+};
+
+#endif  // CHROME_BROWSER_RENDERER_HOST_CHROME_NAVIGATION_DATA_H_