chromium/components/page_load_metrics/browser/observers/early_hints_page_load_metrics_observer.h

// Copyright 2021 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef COMPONENTS_PAGE_LOAD_METRICS_BROWSER_OBSERVERS_EARLY_HINTS_PAGE_LOAD_METRICS_OBSERVER_H_
#define COMPONENTS_PAGE_LOAD_METRICS_BROWSER_OBSERVERS_EARLY_HINTS_PAGE_LOAD_METRICS_OBSERVER_H_

#include "components/page_load_metrics/browser/page_load_metrics_observer.h"

namespace internal {

extern const char kHistogramEarlyHintsPreloadFirstContentfulPaint[];
extern const char kHistogramEarlyHintsPreloadLargestContentfulPaint[];
extern const char kHistogramEarlyHintsPreloadFirstInputDelay[];

}  // namespace internal

// Records custom page load timing metrics for pages that received preload Link
// headers via Early Hints responses.
class EarlyHintsPageLoadMetricsObserver
    : public page_load_metrics::PageLoadMetricsObserver { … };

#endif  // COMPONENTS_PAGE_LOAD_METRICS_BROWSER_OBSERVERS_EARLY_HINTS_PAGE_LOAD_METRICS_OBSERVER_H_