Revert of Add SafeBrowsingNavigationObserver to listen to navigation events

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 "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
-#include "content/public/browser/web_contents_observer.h"
-#include "url/gurl.h"
-
-namespace content {
-class NavigationHandle;
-struct ResourceRedirectDetails;
-}
-
-namespace safe_browsing {
-
-class SafeBrowsingNavigationObserver;
-struct NavigationEvent;
-struct ResolvedIPAddress;
-
-// Manager class for SafeBrowsingNavigationObserver, which is in charge of
-// cleaning up stale navigation events, and identifing landing page/landing
-// referrer for a specific download.
-// TODO(jialiul): For now, SafeBrowsingNavigationObserverManager also listens to
-// NOTIFICATION_RETARGETING as a way to detect cross frame/tab navigation.
-// Remove base class content::NotificationObserver when
-// WebContentsObserver::DidOpenRequestedURL() covers all retargeting cases.
-class SafeBrowsingNavigationObserverManager
-    : public content::NotificationObserver,
-      public base::RefCountedThreadSafe<SafeBrowsingNavigationObserverManager> {
- public:
-  // 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);
-
-  SafeBrowsingNavigationObserverManager();
-
-  // Add |nav_event| to |navigation_map_| based on |nav_event_key|. Object
-  // pointed to by |nav_event| will be no longer accessible after this function.
-  void RecordNavigationEvent(const GURL& nav_event_key,
-                             NavigationEvent* nav_event);
-  void RecordUserGestureForWebContents(content::WebContents* web_contents,
-                                       const base::Time& timestamp);
-  void OnUserGestureConsumed(content::WebContents* web_contents,
-                             const base::Time& timestamp);
-  void RecordHostToIpMapping(const std::string& host, const std::string& ip);
-  // Clean-ups need to be done when a WebContents gets destroyed.
-  void OnWebContentDestroyed(content::WebContents* web_contents);
-
-  // TODO(jialiul): more functions are coming for managing navigation_map_.
-
- private:
-  friend class base::RefCountedThreadSafe<
-      SafeBrowsingNavigationObserverManager>;
-  friend class TestNavigationObserverManager;
-  friend class SBNavigationObserverBrowserTest;
-  friend class SBNavigationObserverTest;
-
-  struct GurlHash {
-    std::size_t operator()(const GURL& url) const {
-      return std::hash<std::string>()(url.spec());
-    }
-  };
-
-  typedef std::unordered_map<GURL, std::vector<NavigationEvent>, GurlHash>
-      NavigationMap;
-  typedef std::unordered_map<content::WebContents*, base::Time> UserGestureMap;
-  typedef std::unordered_map<std::string, std::vector<ResolvedIPAddress>>
-      HostToIpMap;
-
-  ~SafeBrowsingNavigationObserverManager() override;
-
-  // content::NotificationObserver:
-  void Observe(int type,
-               const content::NotificationSource& source,
-               const content::NotificationDetails& details) override;
-
-  void RecordRetargeting(const content::NotificationDetails& details);
-
-  NavigationMap* navigation_map() { return &navigation_map_; }
-
-  HostToIpMap* host_to_ip_map() { return &host_to_ip_map_; }
-
-  // navigation_map_ keeps track of all the observed navigations. This map is
-  // keyed on the resolved request url. In other words, in case of server
-  // redirects, its key is the last server redirect url, otherwise, it is the
-  // original target url. Since the same url can be requested multiple times
-  // across different tabs and frames, the value of this map is a vector of
-  // NavigationEvent ordered by navigation finish time.
-  // TODO(jialiul): Entries in navigation_map_ will be removed if they are older
-  // than 2 minutes since their corresponding navigations finish.
-  NavigationMap navigation_map_;
-
-  // user_gesture_map_ keeps track of the timestamp of last user gesture in
-  // in each WebContents. We assume for majority of cases, a navigation
-  // shortly after a user gesture indicate this navigation is user initiated.
-  UserGestureMap user_gesture_map_;
-
-  // Host to timestamped IP addresses map that covers all the main frame and
-  // subframe URLs' hosts. Since it is possible for a host to resolve to more
-  // than one IP in even a short period of time, we map a single host to a
-  // vector of ResolvedIPAddresss. This map is used to fill in ip_address field
-  // in URLChainEntry in ClientDownloadRequest.
-  HostToIpMap host_to_ip_map_;
-
-  content::NotificationRegistrar registrar_;
-
-  DISALLOW_COPY_AND_ASSIGN(SafeBrowsingNavigationObserverManager);
-};
-}  // namespace safe_browsing
-
-#endif  // CHROME_BROWSER_SAFE_BROWSING_SAFE_BROWSING_NAVIGATION_OBSERVER_MANAGER_H_