chromium/src/third_party/blink/public/mojom/feature_observer/feature_observer.mojom

// Copyright 2020 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.

module blink.mojom;

enum ObservedFeatureType {
  kWebLock = 0,
  kIndexedDBConnection,
};

// An interface tied to the lifetime of a feature's usage.
interface ObservedFeature {};

// A generic interface for informing some remote that a given feature has
// begun or ended.  This is for purposes such as tab freezing, which wants to
// avoid freezing tabs that are using particular features.  This interface
// is implemented by the browser process so the renderer can inform it about
// feature usage.
interface FeatureObserver {
  // Inform the observer that a particular |feature| is being used, and
  // when the connection is broken, that instance is no longer in use.
  Register(pending_receiver<ObservedFeature> feature, ObservedFeatureType type);
};