PageLoadMetrics renderer and browser implementation.

components/page_load_metrics/common/page_load_timing.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/common/page_load_timing.h"
+#include "third_party/WebKit/public/web/WebPerformance.h"
+
+namespace page_load_metrics {
+
+namespace {
+
+base::TimeDelta ClampDelta(double event_ms, double start_ms) {
+  double delta = event_ms - start_ms;
+  return base::TimeDelta::FromMillisecondsD(delta < 0 ? 0 : delta);
+}
+
+}  // namespace
+
+PageLoadTiming::PageLoadTiming() {}
+PageLoadTiming::PageLoadTiming(const blink::WebPerformance& perf) {

[Bryan McQuade, 2015/09/10 00:45:58]

let's insert a newline between the 2 constructor definitions

[Charlie Harrison, 2015/09/10 19:22:41]

Done.

+  double start = perf.navigationStart();
+  navigation_start = base::Time::FromDoubleT(start);
+  response_start = ClampDelta(perf.responseStart(), start);
+  dom_content_loaded_event_start =
+      ClampDelta(perf.domContentLoadedEventStart(), start);
+  load_event_start = ClampDelta(perf.loadEventStart(), start);
+  first_layout = ClampDelta(perf.firstLayout(), start);
+}
+
+PageLoadTiming::~PageLoadTiming() {}
+
+bool PageLoadTiming::operator==(const PageLoadTiming& other) const {
+  return navigation_start == other.navigation_start &&
+         response_start == other.response_start &&
+         dom_content_loaded_event_start ==
+             other.dom_content_loaded_event_start &&
+         load_event_start == other.load_event_start &&
+         first_layout == other.first_layout;
+}
+
+bool PageLoadTiming::IsEmpty() const {
+  return navigation_start.is_null() && response_start.is_zero() &&
+         dom_content_loaded_event_start.is_zero() &&
+         load_event_start.is_zero() && first_layout.is_zero();
+}
+}  // namespace page_load_metrics