Adding DRP specfic UMA for FirstContentfulPaint

components/page_load_metrics/browser/page_load_metrics_observer.h

Index: components/page_load_metrics/browser/page_load_metrics_observer.h
diff --git a/components/page_load_metrics/browser/page_load_metrics_observer.h b/components/page_load_metrics/browser/page_load_metrics_observer.h
index 06705b20fe179ce8d258049929dde4531beb9554..1c5522b4e87c466cdd4bacd4b1e3e320082c8bae 100644
--- a/components/page_load_metrics/browser/page_load_metrics_observer.h
+++ b/components/page_load_metrics/browser/page_load_metrics_observer.h
@@ -46,21 +46,23 @@ enum UserAbortType {
   ABORT_LAST_ENTRY
 };
 
 struct PageLoadExtraInfo {
   PageLoadExtraInfo(const base::TimeDelta& first_background_time,
                     const base::TimeDelta& first_foreground_time,
                     bool started_in_foreground,
                     const GURL& committed_url,
                     const base::TimeDelta& time_to_commit,
                     UserAbortType abort_type,
-                    const base::TimeDelta& time_to_abort);
+                    const base::TimeDelta& time_to_abort,
+                    bool is_using_lofi,
+                    bool was_fetched_via_data_reduction_proxy);

[bengr, 2016/02/26 22:53:57]

That's a mouthful. How about used_data_reduction_proxy? If you make the change,
do so everywhere.

[RyanSturm, 2016/03/01 19:36:04]

Done.

 
   // Returns the time to first background if the page load started in the
   // foreground. If the page has not been backgrounded, or the page started in
   // the background, this will be base::TimeDelta().
   const base::TimeDelta first_background_time;
 
   // Returns the time to first foreground if the page load started in the
   // background. If the page has not been foregrounded, or the page started in
   // the foreground, this will be base::TimeDelta().
   const base::TimeDelta first_foreground_time;
@@ -74,20 +76,23 @@ struct PageLoadExtraInfo {
 
   // Time from navigation start until commit. If the page load did not commit,
   // |time_to_commit| will be zero.
   const base::TimeDelta time_to_commit;
 
   // The abort time and time to abort for this page load. If the page was not
   // aborted, |abort_type| will be |ABORT_NONE| and |time_to_abort| will be
   // |base::TimeDelta()|.
   const UserAbortType abort_type;
   const base::TimeDelta time_to_abort;
+
+  bool is_using_lofi;

[bengr, 2016/02/26 22:53:57]

Add comments to describe these.

[RyanSturm, 2016/03/01 19:36:04]

Done.

+  bool was_fetched_via_data_reduction_proxy;
 };
 
 // Interface for PageLoadMetrics observers. All instances of this class are
 // owned by the PageLoadTracker tracking a page load. They will be deleted after
 // calling OnComplete.
 class PageLoadMetricsObserver {
  public:
   virtual ~PageLoadMetricsObserver() {}
 
   // The page load started, with the given navigation handle.