Adding a DataSavingsRecorder interface

components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.h

Index: components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.h
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.h b/components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.h
index fb91fd35e0146fc1695ca8b9f7e2b1fd02b73c58..26f40fb9780b20380a460894282323d0590d78b6 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.h
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.h
@@ -2,21 +2,20 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_DATA_REDUCTION_PROXY_CORE_BROWSER_DATA_REDUCTION_PROXY_METRICS_H_
 #define COMPONENTS_DATA_REDUCTION_PROXY_CORE_BROWSER_DATA_REDUCTION_PROXY_METRICS_H_
 
 #include <stdint.h>
 
 #include <vector>
 
-
 namespace net {
 class ProxyConfig;
 class URLRequest;
 }
 
 class PrefService;
 
 namespace data_reduction_proxy {
 
 typedef std::vector<long long> ContentLengthList;
@@ -31,27 +30,27 @@ const unsigned int kNumDaysInHistory = 60;
 
 // The number of days of bandwidth usage statistics that are presented.
 const unsigned int kNumDaysInHistorySummary = 30;
 
 static_assert(kNumDaysInHistorySummary <= kNumDaysInHistory,
               "kNumDaysInHistorySummary should be no larger than "
               "kNumDaysInHistory");
 
 enum DataReductionProxyRequestType {
   VIA_DATA_REDUCTION_PROXY,  // A request served by the data reduction proxy.
-
   // Below are reasons why a request is not served by the enabled data reduction
   // proxy. Off-the-record profile data is not counted in all cases.
-  HTTPS,  // An https request.
+  HTTPS,         // An https request.
   SHORT_BYPASS,  // The client is bypassed by the proxy for a short time.
-  LONG_BYPASS,  // The client is bypassed by the proxy for a long time (due
-                // to country bypass policy, for example).
+  LONG_BYPASS,   // The client is bypassed by the proxy for a long time (due
+                 // to country bypass policy, for example).
+  UPDATE,        // An update to already counted request data.
   UNKNOWN_TYPE,  // Any other reason not listed above.
 };
 
 // Returns DataReductionProxyRequestType for |request|.
 DataReductionProxyRequestType GetDataReductionProxyRequestType(
     const net::URLRequest& request,
     const net::ProxyConfig& data_reduction_proxy_config,
     const DataReductionProxyConfig& config);
 
 // Returns |received_content_length| as adjusted original content length if