Optional <TimeDelta> since they may be non existent.

components/page_load_metrics/browser/page_load_metrics_util.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/page_load_metrics/browser/page_load_metrics_util.h"
 
 #include <algorithm>
 
 #include "components/page_load_metrics/browser/page_load_metrics_observer.h"
 #include "components/page_load_metrics/common/page_load_timing.h"
 
 namespace page_load_metrics {
 
 bool WasStartedInForegroundEventInForeground(base::TimeDelta event,
                                              const PageLoadExtraInfo& info) {
   return info.started_in_foreground && !event.is_zero() &&
-         (info.first_background_time.is_zero() ||
-          event < info.first_background_time);
+         (!info.first_background_time ||
+          event <= info.first_background_time.value());
+}
+
+// TODO (@shivanisha) Since the above function is called for

[Charlie Harrison, 2016/05/19 18:20:49]

"TODO(shivanisha):" Is the preferred syntax.

+// TimeDelta coming over IPC (PageLoadTiming) and since Optional is not

[Charlie Harrison, 2016/05/19 18:20:49]

This sentence is a little awkward. What about:

"The above function is only used for TimeDeltas coming over IPC. Merge these two
when page_load_metrics only handles Optional values in the browser process.

[shivanisha, 2016/05/23 15:06:44]

sounds good. done

+// currently supported in IPC, thus creating another function.
+// They should ideally converge to one function in the future
+// when either the serialization framework supports Optional or we send
+// actual timestamps over IPC and compute deltas in browser process.
+bool WasStartedInForegroundOptionalEventInForeground(
+    const base::Optional<base::TimeDelta>& event,
+    const PageLoadExtraInfo& info) {
+  return info.started_in_foreground && event &&
+         (!info.first_background_time ||
+          event.value() <= info.first_background_time.value());
 }
 
 bool WasParseInForeground(base::TimeDelta parse_start,
                           base::TimeDelta parse_stop,
                           const PageLoadExtraInfo& info) {
   if (parse_start.is_zero()) {
     return false;
   }
-  const bool incomplete_parse_in_foreground =
-      parse_stop.is_zero() && info.started_in_foreground &&
-      info.first_background_time.is_zero();
+  const bool incomplete_parse_in_foreground = parse_stop.is_zero() &&
+                                              info.started_in_foreground &&
+                                              !info.first_background_time;
 
   return incomplete_parse_in_foreground ||
          WasStartedInForegroundEventInForeground(parse_stop, info);
 }
 }  // namespace page_load_metrics