[subresource_filter] Use the SubresourceFilterObserver for PageLoadMetrics

chrome/browser/subresource_filter/chrome_subresource_filter_client.cc

 // Copyright 2016 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/chrome_subresource_filter_client.h"
 
 #include <string>
 #include <utility>
 
 #include "base/feature_list.h"
@@ skipping 34 matching lines @@
   settings_manager_ = context->settings_manager();
   subresource_filter::ContentSubresourceFilterDriverFactory::
       CreateForWebContents(web_contents, this);
 }
 
 ChromeSubresourceFilterClient::~ChromeSubresourceFilterClient() {}
 
 void ChromeSubresourceFilterClient::MaybeAppendNavigationThrottles(
     content::NavigationHandle* navigation_handle,
     std::vector<std::unique_ptr<content::NavigationThrottle>>* throttles) {
-  // Don't add any throttles if the feature isn't enabled at all.
-  if (!base::FeatureList::IsEnabled(
-          subresource_filter::kSafeBrowsingSubresourceFilter)) {
-    return;
-  }
-
   if (navigation_handle->IsInMainFrame()) {
     safe_browsing::SafeBrowsingService* safe_browsing_service =
         g_browser_process->safe_browsing_service();
     scoped_refptr<safe_browsing::SafeBrowsingDatabaseManager> database_manager;
     if (safe_browsing_service &&
         safe_browsing_service->database_manager()->IsSupported() &&
         safe_browsing::V4FeatureList::GetV4UsageStatus() ==
             safe_browsing::V4FeatureList::V4UsageStatus::V4_ONLY) {
       database_manager = safe_browsing_service->database_manager();
     }
@@ skipping 96 matching lines @@
   UMA_HISTOGRAM_ENUMERATION("SubresourceFilter.Actions", action,
                             kActionLastEntry);
 }
 
 subresource_filter::VerifiedRulesetDealer::Handle*
 ChromeSubresourceFilterClient::GetRulesetDealer() {
   subresource_filter::ContentRulesetService* ruleset_service =
       g_browser_process->subresource_filter_ruleset_service();
   return ruleset_service ? ruleset_service->ruleset_dealer() : nullptr;
 }