Add support for time based deletion of browsing data on iOS

ios/chrome/browser/browsing_data/ios_chrome_browsing_data_remover.mm

 // Copyright 2015 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 "ios/chrome/browser/browsing_data/ios_chrome_browsing_data_remover.h"
 
 #include <map>
 #include <set>
 #include <string>
 
@@ skipping 72 matching lines @@
 IOSChromeBrowsingDataRemover::NotificationDetails::NotificationDetails(
     base::Time removal_begin,
     int removal_mask)
     : removal_begin(removal_begin), removal_mask(removal_mask) {}
 
 IOSChromeBrowsingDataRemover::NotificationDetails::~NotificationDetails() {}
 
 // Static.
 IOSChromeBrowsingDataRemover* IOSChromeBrowsingDataRemover::CreateForPeriod(
     ios::ChromeBrowserState* browser_state,
-    TimePeriod period) {
+    browsing_data::TimePeriod period) {
   switch (period) {
-    case EVERYTHING:
+    case browsing_data::LAST_HOUR:
+      base::RecordAction(UserMetricsAction("ClearBrowsingData_LastHour"));
+      break;
+    case browsing_data::LAST_DAY:
+      base::RecordAction(UserMetricsAction("ClearBrowsingData_LastDay"));
+      break;
+    case browsing_data::LAST_WEEK:
+      base::RecordAction(UserMetricsAction("ClearBrowsingData_LastWeek"));
+      break;
+    case browsing_data::FOUR_WEEKS:
+      base::RecordAction(UserMetricsAction("ClearBrowsingData_LastMonth"));
+      break;
+    case browsing_data::ALL_TIME:
       base::RecordAction(UserMetricsAction("ClearBrowsingData_Everything"));
       break;
   }
   return new IOSChromeBrowsingDataRemover(
-      browser_state,
-      IOSChromeBrowsingDataRemover::CalculateBeginDeleteTime(period),
+      browser_state, browsing_data::CalculateBeginDeleteTime(period),
       base::Time::Max());
 }
 
 IOSChromeBrowsingDataRemover::IOSChromeBrowsingDataRemover(
     ios::ChromeBrowserState* browser_state,
     base::Time delete_begin,
     base::Time delete_end)
     : browser_state_(browser_state),
       delete_begin_(delete_begin),
       delete_end_(delete_end),
@@ skipping 80 matching lines @@
         waiting_for_clear_keyword_data_ = true;
       } else if (keywords_model) {
         keywords_model->RemoveAutoGeneratedForOriginBetween(
             GURL(), delete_begin_, delete_end_);
       }
     }
 
     // If the caller is removing history for all hosts, then clear ancillary
     // historical information.
     // We also delete the list of recently closed tabs. Since these expire,
     // they can't be more than a day old, so we can simply clear them all.

[droger, 2016/08/30 13:00:48]

Should this be changed to avoid deleting everything, especially in the LAST_HOUR
case?

[msramek, 2016/08/30 14:14:35]

This implementation is consistent with Desktop and Android, where we always wipe
the last session (even during LAST_HOUR deletions).

It would be possible to honor timestamps, but it would lead to strange results -
e.g. we would remove some tabs from the session; from those that remain, we
would remove only the latest navigation history... this is probably not the
desired effect.

Furthermore, this should be kept in sync with the session stored on disk (as
opposed to "recent tabs" in memory), and that's a lot more complicated.

     sessions::TabRestoreService* tab_service =
         IOSChromeTabRestoreServiceFactory::GetForBrowserState(browser_state_);
     if (tab_service) {
       tab_service->ClearEntries();
       tab_service->DeleteLastSession();
     }
 
     // The saved Autofill profiles and credit cards can include the origin from
     // which these profiles and credit cards were learned.  These are a form of
     // history, so clear them as well.
@@ skipping 84 matching lines @@
               browser_state_);
       if (data_manager)
         data_manager->Refresh();
     }
   }
 
   if (remove_mask & REMOVE_CACHE) {
     base::RecordAction(UserMetricsAction("ClearBrowsingData_Cache"));
 
     waiting_for_clear_cache_ = true;
-    DCHECK(delete_begin_.is_null()) << "Partial clearing not supported";
     ClearHttpCache(browser_state_->GetRequestContext(),
                    WebThread::GetTaskRunnerForThread(WebThread::IO),
+                   delete_begin_, delete_end_,
                    base::Bind(&IOSChromeBrowsingDataRemover::OnClearedCache,
                               base::Unretained(this)));
   }
 
   // Remove omnibox zero-suggest cache results.
   if ((remove_mask & (REMOVE_CACHE | REMOVE_COOKIES))) {
     browser_state_->GetPrefs()->SetString(omnibox::kZeroSuggestCachedResults,
                                           std::string());
   }
 
@@ skipping 24 matching lines @@
 
 void IOSChromeBrowsingDataRemover::RemoveObserver(Observer* observer) {
   observer_list_.RemoveObserver(observer);
 }
 
 void IOSChromeBrowsingDataRemover::OnHistoryDeletionDone() {
   waiting_for_clear_history_ = false;
   NotifyAndDeleteIfDone();
 }
 
-base::Time IOSChromeBrowsingDataRemover::CalculateBeginDeleteTime(
-    TimePeriod time_period) {
-  base::TimeDelta diff;
-  base::Time delete_begin_time = base::Time::Now();
-  switch (time_period) {
-    case EVERYTHING:
-      delete_begin_time = base::Time();
-      break;
-    default:
-      NOTREACHED() << L"Missing item";
-      break;
-  }
-  return delete_begin_time - diff;
-}
-
 bool IOSChromeBrowsingDataRemover::AllDone() {
   return !waiting_for_clear_autofill_origin_urls_ &&
          !waiting_for_clear_cache_ && !waiting_for_clear_channel_ids_ &&
          !waiting_for_clear_cookies_count_ && !waiting_for_clear_form_ &&
          !waiting_for_clear_history_ &&
          !waiting_for_clear_hostname_resolution_cache_ &&
          !waiting_for_clear_keyword_data_ &&
          !waiting_for_clear_networking_history_ &&
          !waiting_for_clear_passwords_;
 }
@@ skipping 129 matching lines @@
   waiting_for_clear_autofill_origin_urls_ = false;
   NotifyAndDeleteIfDone();
 }
 
 // static
 IOSChromeBrowsingDataRemover::CallbackSubscription
 IOSChromeBrowsingDataRemover::RegisterOnBrowsingDataRemovedCallback(
     const IOSChromeBrowsingDataRemover::Callback& callback) {
   return GetOnBrowsingDataRemovedCallbacks()->Add(callback);
 }