Optional <TimeDelta> since they may be non existent.

components/page_load_metrics/browser/metrics_web_contents_observer.cc

Index: components/page_load_metrics/browser/metrics_web_contents_observer.cc
diff --git a/components/page_load_metrics/browser/metrics_web_contents_observer.cc b/components/page_load_metrics/browser/metrics_web_contents_observer.cc
index 94528773f8549445bc1188541819f3a6ebf81317..b0815342ed5259f53455439171542bd602fc1350 100644
--- a/components/page_load_metrics/browser/metrics_web_contents_observer.cc
+++ b/components/page_load_metrics/browser/metrics_web_contents_observer.cc
@@ -191,9 +191,9 @@ PageLoadTracker::PageLoadTracker(
 }
 
 PageLoadTracker::~PageLoadTracker() {
-  const PageLoadExtraInfo info = GetPageLoadMetricsInfo();
-  if (!info.time_to_commit.is_zero() && renderer_tracked() &&
-      timing_.IsEmpty()) {
+  const PageLoadExtraInfo info = ComputePageLoadExtraInfo();
+
+  if (!info.time_to_commit && renderer_tracked() && timing_.IsEmpty()) {
     RecordInternalError(ERR_NO_IPCS_RECEIVED);
   }
   // Recall that trackers that are given ABORT_UNKNOWN_NAVIGATION have their
@@ -326,27 +326,25 @@ void PageLoadTracker::AddObserver(
   observers_.push_back(std::move(observer));
 }
 
-PageLoadExtraInfo PageLoadTracker::GetPageLoadMetricsInfo() {
-  base::TimeDelta first_background_time;
-  base::TimeDelta first_foreground_time;
-  base::TimeDelta time_to_abort;
-  base::TimeDelta time_to_commit;
+PageLoadExtraInfo PageLoadTracker::ComputePageLoadExtraInfo() {
+  base::Optional<base::TimeDelta> first_background_time;
+  base::Optional<base::TimeDelta> first_foreground_time;
+  base::Optional<base::TimeDelta> time_to_abort;
+  base::Optional<base::TimeDelta> time_to_commit;
   if (!background_time_.is_null())
     first_background_time = background_time_ - navigation_start_;
   if (!foreground_time_.is_null())
     first_foreground_time = foreground_time_ - navigation_start_;
   if (abort_type_ != ABORT_NONE) {
-    DCHECK_GT(abort_time_, navigation_start_);
+    DCHECK_GE(abort_time_, navigation_start_);
     time_to_abort = abort_time_ - navigation_start_;
   } else {
     DCHECK(abort_time_.is_null());
   }
 
   if (!commit_time_.is_null()) {
-    DCHECK_GT(commit_time_, navigation_start_);
+    DCHECK_GE(commit_time_, navigation_start_);
     time_to_commit = commit_time_ - navigation_start_;
-  } else {
-    DCHECK(commit_time_.is_null());
   }
   return PageLoadExtraInfo(first_background_time, first_foreground_time,
                            started_in_foreground_,
@@ -402,7 +400,7 @@ void PageLoadTracker::UpdateAbortInternal(UserAbortType abort_type,
   // infer the cause of aborts. It would be better if the navigation code could
   // instead report the actual cause of an aborted navigation. See crbug/571647
   // for details.
-  if (timestamp <= navigation_start_) {
+  if (timestamp < navigation_start_) {
     RecordInternalError(ERR_ABORT_BEFORE_NAVIGATION_START);
     abort_type_ = ABORT_NONE;
     abort_time_ = base::TimeTicks();