Send an event to the page load metrics to track resource starting.

chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.cc

Index: chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.cc
diff --git a/chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.cc b/chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.cc
index c9e3c30577c3848f4243cb2cdddcc432700d313e..d1fbb2f7aa3a3358b6942aab0701a8308a8fac4e 100644
--- a/chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.cc
+++ b/chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.cc
@@ -419,23 +419,25 @@ void DataReductionProxyMetricsObserver::OnParseStop(
 }
 
 void DataReductionProxyMetricsObserver::OnLoadedResource(
-    const page_load_metrics::ExtraRequestInfo& extra_request_info) {
-  if (extra_request_info.data_reduction_proxy_data &&
-      extra_request_info.data_reduction_proxy_data->lofi_received()) {
+    const page_load_metrics::ExtraRequestCompleteInfo&
+        extra_request_complete_info) {
+  if (extra_request_complete_info.data_reduction_proxy_data &&
+      extra_request_complete_info.data_reduction_proxy_data->lofi_received()) {
     data_->set_lofi_received(true);
   }
-  if (extra_request_info.was_cached)
+  if (extra_request_complete_info.was_cached)
     return;
-  original_network_bytes_ += extra_request_info.original_network_content_length;
-  network_bytes_ += extra_request_info.raw_body_bytes;
+  original_network_bytes_ +=
+      extra_request_complete_info.original_network_content_length;
+  network_bytes_ += extra_request_complete_info.raw_body_bytes;
   num_network_resources_++;
-  if (!extra_request_info.data_reduction_proxy_data ||
-      !extra_request_info.data_reduction_proxy_data
+  if (!extra_request_complete_info.data_reduction_proxy_data ||
+      !extra_request_complete_info.data_reduction_proxy_data
            ->used_data_reduction_proxy()) {
     return;
   }
   num_data_reduction_proxy_resources_++;
-  network_bytes_proxied_ += extra_request_info.raw_body_bytes;
+  network_bytes_proxied_ += extra_request_complete_info.raw_body_bytes;
 }
 
 DataReductionProxyPingbackClient*