tab_load_tracker.h | Explore in Territory

// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CHROME_BROWSER_RESOURCE_COORDINATOR_TAB_LOAD_TRACKER_H_
#define CHROME_BROWSER_RESOURCE_COORDINATOR_TAB_LOAD_TRACKER_H_

#include "base/containers/flat_map.h"
#include "base/functional/callback.h"
#include "base/gtest_prod_util.h"
#include "base/observer_list.h"
#include "base/process/kill.h"
#include "base/sequence_checker.h"
#include "chrome/browser/resource_coordinator/lifecycle_unit_state.mojom-shared.h"

namespace content {
class WebContents;
}  // namespace content

namespace resource_coordinator {

class ResourceCoordinatorParts;
class ResourceCoordinatorTabHelper;

// DEPRECATED. New users must observe PageNode::IsLoading() with a
// PageNodeObserver. For guidance: //components/performance_manager/OWNERS
//
// This class has the sole purpose of tracking the state of all tab-related
// WebContents, and whether or not they are in an unloaded, currently loading,
// or loaded state.
//
// This class must be bound to a given Sequence and all access to it must occur
// on that Sequence. In practice, this is intended to be on the UI thread as the
// notifications of interest occur natively on that thread. All calculations are
// very short and quick, so it is suitable for use on that thread.
//
// This class is intended to be created in early startup and persists as a
// singleton in the browser process. It is deliberately leaked at shutdown.
//
// This class isn't directly an observer of anything. An external source must
// invoke the callbacks in the protected section of the class. In the case of
// the TabManager this is done by a combination of the
// ResourceCoordinatorTabHelper and the
// TabManagerResourceCoordinatorSignalObserver.
class TabLoadTracker { … };

// A class for observing loading state changes of WebContents under observation
// by a given TabLoadTracker. All of the callbacks will be invoked on the
// sequence to which the TabLoadTracker is bound.
class TabLoadTracker::Observer { … };

}  // namespace resource_coordinator

#endif  // CHROME_BROWSER_RESOURCE_COORDINATOR_TAB_LOAD_TRACKER_H_
chromium/chrome/browser/resource_coordinator/tab_load_tracker.h
