Upload UMA data using protocol buffers.

chrome/browser/metrics/metrics_service.h

Index: chrome/browser/metrics/metrics_service.h
diff --git a/chrome/browser/metrics/metrics_service.h b/chrome/browser/metrics/metrics_service.h
index 56f9776863e6dc0f45ea1a05696e1956d2055b3f..8803905b5cec95b53d312b45b5af8a9a842c2e46 100644
--- a/chrome/browser/metrics/metrics_service.h
+++ b/chrome/browser/metrics/metrics_service.h
@@ -340,10 +340,18 @@ class MetricsService : public content::NotificationObserver,
   std::vector<webkit::WebPluginInfo> plugins_;
 
   // The outstanding transmission appears as a URL Fetch operation.
-  scoped_ptr<content::URLFetcher> current_fetch_;
-
-  // The URL for the metrics server.
-  std::wstring server_url_;
+  scoped_ptr<content::URLFetcher> current_fetch_xml_;
+  scoped_ptr<content::URLFetcher> current_fetch_proto_;
+
+  // Cached responses from the XML request while we wait for a response to the
+  // protubuf request.
+  int response_code_;
+  std::string response_status_;
+  std::string response_data_;
+
+  // The URLs for the XML and protobuf metrics servers.
+  string16 server_url_xml_;
+  string16 server_url_proto_;
 
   // The TCP/UDP echo server to collect network connectivity stats.
   std::string network_stats_server_;