Adding DRP specfic UMA for FirstContentfulPaint

components/data_reduction_proxy/core/browser/data_reduction_proxy_data.cc

Index: components/data_reduction_proxy/core/browser/data_reduction_proxy_data.cc
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_data.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_data.cc
new file mode 100644
index 0000000000000000000000000000000000000000..eaf5533a888603a1e66f27b124949dcbdcb21c6c
--- /dev/null
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_data.cc
@@ -0,0 +1,41 @@
+// 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.
+
+#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_data.h"
+
+#include "net/url_request/url_request.h"
+
+namespace data_reduction_proxy {
+
+const void* const kDataReductionProxyUserDataKey =
+    &kDataReductionProxyUserDataKey;
+
+DataReductionProxyData::DataReductionProxyData()
+    : used_data_reduction_proxy_(false), is_using_lofi_(false) {}
+
+std::unique_ptr<DataReductionProxyData> DataReductionProxyData::DeepCopy()
+    const {
+  std::unique_ptr<DataReductionProxyData> copy(new DataReductionProxyData());
+  copy->used_data_reduction_proxy_ = used_data_reduction_proxy_;
+  copy->is_using_lofi_ = is_using_lofi_;
+  return copy;
+}
+
+DataReductionProxyData* DataReductionProxyData::DataForRequest(
+    net::URLRequest* request,

[tbansal1, 2016/04/27 23:44:48]

Better to pass |request| by const ref. That makes it clearer that the function
is not going to modify |request|.

+    bool add_if_not_exist) {
+  if (!request)
+    return nullptr;
+  DataReductionProxyData* data = static_cast<DataReductionProxyData*>(
+      request->GetUserData(kDataReductionProxyUserDataKey));
+  if (data)
+    return data;
+  if (!add_if_not_exist)
+    return nullptr;
+  data = new DataReductionProxyData();
+  request->SetUserData(kDataReductionProxyUserDataKey, data);
+  return data;
+}
+
+}  // namespace data_reduction_proxy