Add the client for accessing Subresource Filter only list.

chrome/browser/subresource_filter/navigation_throttle_util.cc

+// Copyright (c) 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.
+
+#include "chrome/browser/subresource_filter/navigation_throttle_util.h"
+
+#include "chrome/browser/safe_browsing/safe_browsing_service.h"
+#include "components/safe_browsing_db/database_manager.h"
+#include "components/safe_browsing_db/v4_feature_list.h"
+#include "components/subresource_filter/content/browser/subresource_filter_safe_browsing_activation_throttle.h"
+#include "components/subresource_filter/core/browser/subresource_filter_features.h"
+#include "content/public/browser/navigation_handle.h"
+
+content::NavigationThrottle* MaybeCreateSubresourceFilterNavigationThrottle(
+    content::NavigationHandle* navigation_handle,
+    safe_browsing::SafeBrowsingService* safe_browsing_service) {
+  bool feature_enabled = base::FeatureList::IsEnabled(
+      subresource_filter::kSubresourceFilterSafeBrowsingActivationThrottle);
+  if (feature_enabled && navigation_handle->IsInMainFrame() &&
+      safe_browsing_service &&
+      safe_browsing_service->database_manager()->IsSupported() &&
+      safe_browsing::V4FeatureList::GetV4UsageStatus() ==
+          safe_browsing::V4FeatureList::V4UsageStatus::V4_ONLY) {
+    return new subresource_filter::
+        SubresourceFilterSafeBrowsingActivationThrottle(
+            navigation_handle, safe_browsing_service->database_manager());
+  }
+  return nullptr;
+}