Clean up DownloadAttribution Finch experiments

chrome/browser/safe_browsing/safe_browsing_navigation_observer_manager.h

 // 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.
 
 #ifndef CHROME_BROWSER_SAFE_BROWSING_SAFE_BROWSING_NAVIGATION_OBSERVER_MANAGER_H_
 #define CHROME_BROWSER_SAFE_BROWSING_SAFE_BROWSING_NAVIGATION_OBSERVER_MANAGER_H_
 
 #include <deque>
 #include "base/feature_list.h"
 #include "base/supports_user_data.h"
@@ skipping 77 matching lines @@
   std::deque<std::unique_ptr<NavigationEvent>> navigation_events_;
   const std::size_t size_limit_;
 };
 
 // Manager class for SafeBrowsingNavigationObserver, which is in charge of
 // cleaning up stale navigation events, and identifying landing page/landing
 // referrer for a specific Safe Browsing event.
 class SafeBrowsingNavigationObserverManager
     : public base::RefCountedThreadSafe<SafeBrowsingNavigationObserverManager> {
  public:
-  static const base::Feature kDownloadAttribution;
-
   // For UMA histogram counting. Do NOT change order.
   enum AttributionResult {
     SUCCESS = 1,                   // Identified referrer chain is not empty.
     SUCCESS_LANDING_PAGE = 2,      // Successfully identified landing page.
     SUCCESS_LANDING_REFERRER = 3,  // Successfully identified landing referrer.
     INVALID_URL = 4,
     NAVIGATION_EVENT_NOT_FOUND = 5,
 
     // Always at the end.
     ATTRIBUTION_FAILURE_TYPE_MAX
   };
 
   // Helper function to check if user gesture is older than
   // kUserGestureTTLInSecond.
   static bool IsUserGestureExpired(const base::Time& timestamp);
 
   // Helper function to strip empty ref fragment from a URL. Many pages
   // end up with a "#" at the end of their URLs due to navigation triggered by
   // href="#" and javascript onclick function. We don't want to have separate
   // entries for these cases in the maps.
   static GURL ClearEmptyRef(const GURL& url);
 
   // Checks if we should enable observing navigations for safe browsing purpose.
-  // Return true if the safe browsing service and the |kDownloadAttribution|
-  // feature are both enabled, and safe browsing service is initialized.
+  // Return true if the safe browsing safe browsing service is enabled and
+  // initialized.
   static bool IsEnabledAndReady(Profile* profile);
 
   SafeBrowsingNavigationObserverManager();
 
   // Adds |nav_event| to |navigation_event_list_|. Object pointed to by
   // |nav_event| will be no longer accessible after this function.
   void RecordNavigationEvent(std::unique_ptr<NavigationEvent> nav_event);
   void RecordUserGestureForWebContents(content::WebContents* web_contents,
                                        const base::Time& timestamp);
   void OnUserGestureConsumed(content::WebContents* web_contents,
@@ skipping 130 matching lines @@
   // vector of ResolvedIPAddresss.
   HostToIpMap host_to_ip_map_;
 
   base::OneShotTimer cleanup_timer_;
 
   DISALLOW_COPY_AND_ASSIGN(SafeBrowsingNavigationObserverManager);
 };
 }  // namespace safe_browsing
 
 #endif  // CHROME_BROWSER_SAFE_BROWSING_SAFE_BROWSING_NAVIGATION_OBSERVER_MANAGER_H_