Adding opt out and previews type information to DRP pingback

chrome/browser/page_load_metrics/page_load_metrics_observer.h

Index: chrome/browser/page_load_metrics/page_load_metrics_observer.h
diff --git a/chrome/browser/page_load_metrics/page_load_metrics_observer.h b/chrome/browser/page_load_metrics/page_load_metrics_observer.h
index 11a98896bd91bf72d28f0f68b05251f2ef5229f3..3ef455d40ee03dbeb56e9ddb9b10f0ae8884578c 100644
--- a/chrome/browser/page_load_metrics/page_load_metrics_observer.h
+++ b/chrome/browser/page_load_metrics/page_load_metrics_observer.h
@@ -200,6 +200,7 @@ struct ExtraRequestInfo {
   ExtraRequestInfo(bool was_cached,
                    int64_t raw_body_bytes,
                    bool data_reduction_proxy_used,
+                   bool was_lofi_response,
                    int64_t original_network_content_length);
 
   ExtraRequestInfo(const ExtraRequestInfo& other);
@@ -215,6 +216,9 @@ struct ExtraRequestInfo {
   // Whether this request used Data Reduction Proxy.
   const bool data_reduction_proxy_used;
 
+  // Whether this request was a Data Reduction Proxy LoFi response.
+  const bool was_lofi_response;
+
   // The number of body (not header) bytes that the data reduction proxy saw
   // before it compressed the requests.
   const int64_t original_network_content_length;