Revert of Use FrameIsAd to decide whether to isolate a frame in TopDocumentIsolation mode.

chrome/browser/page_load_metrics/ads_detection.h

-// Copyright 2017 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.
-
-#ifndef CHROME_BROWSER_PAGE_LOAD_METRICS_ADS_DETECTION_H_
-#define CHROME_BROWSER_PAGE_LOAD_METRICS_ADS_DETECTION_H_
-
-#include <bitset>
-
-namespace content {
-class NavigationHandle;
-}  // namespace content
-
-namespace page_load_metrics {
-
-// The types of ads that one can detect or filter on.
-enum AdType {
-  AD_TYPE_GOOGLE = 0,
-  AD_TYPE_SUBRESOURCE_FILTER = 1,
-  AD_TYPE_ALL = 2,
-  AD_TYPE_MAX = AD_TYPE_ALL
-};
-using AdTypes = std::bitset<AD_TYPE_MAX>;
-
-// Uses heuristics to determine if |navigation_handle| is a navigation for an
-// ad.  Must be called no earlier than
-// NavigationHandleImpl::ReadyToCommitNavigation.
-const AdTypes& GetDetectedAdTypes(content::NavigationHandle* navigation_handle);
-
-// Marks the |navigation_handle| as loading an advertisment of a given |type|.
-void SetDetectedAdType(content::NavigationHandle* navigation_handle,
-                       AdType type);
-
-}  // namespace page_load_metrics
-
-#endif  // CHROME_BROWSER_PAGE_LOAD_METRICS_ADS_DETECTION_H_