[MD settings] disable clear browsing data while it is running

chrome/browser/browsing_data/browsing_data_remover.cc

 // Copyright (c) 2012 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/browsing_data/browsing_data_remover.h"
 
 #include <map>
 #include <set>
 #include <string>
 
@@ skipping 328 matching lines @@
 }
 
 void BrowsingDataRemover::Shutdown() {
   history_task_tracker_.TryCancelAll();
   template_url_sub_.reset();
 }
 
 void BrowsingDataRemover::SetRemoving(bool is_removing) {
   DCHECK_NE(is_removing_, is_removing);
   is_removing_ = is_removing;
+  FOR_EACH_OBSERVER(Observer, observer_list_,
+                    OnBrowsingDataRemoving(is_removing));
 }
 
 void BrowsingDataRemover::Remove(const TimeRange& time_range,
                                  int remove_mask,
                                  int origin_type_mask) {
   // Any instance of BrowsingDataFilterBuilder that |IsEmptyBlacklist()|
   // is OK to pass here.
   RegistrableDomainFilterBuilder builder(
       RegistrableDomainFilterBuilder::BLACKLIST);
   DCHECK(builder.IsEmptyBlacklist());
@@ skipping 954 matching lines @@
   waiting_for_clear_domain_reliability_monitor_ = false;
   NotifyIfDone();
 }
 
 // static
 BrowsingDataRemover::CallbackSubscription
     BrowsingDataRemover::RegisterOnBrowsingDataRemovedCallback(
         const BrowsingDataRemover::Callback& callback) {
   return GetOnBrowsingDataRemovedCallbacks()->Add(callback);
 }