Remove all but one use of WeakPtrFactory::DetachFromThread.

chrome/browser/extensions/api/declarative/rules_registry_with_cache.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/extensions/api/declarative/rules_registry_with_cache.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
 #include "base/metrics/histogram.h"
@@ skipping 79 matching lines @@
                                                  log_storage_init_delay))
                                 ->GetWeakPtr()
                           : base::WeakPtr<RuleStorageOnUI>())) {
   if (!profile) {
     CHECK(!ui_part);
     return;
   }
 
   ui_part->reset(storage_on_ui_.get());
 
-  // After construction, |this| continues to live only on |owner_thread|.
-  weak_ptr_factory_.DetachFromThread();
-
   storage_on_ui_->Init();
 }
 
 void RulesRegistryWithCache::AddReadyCallback(const base::Closure& callback) {
   ready_callbacks_.push_back(callback);
 }
 
 std::string RulesRegistryWithCache::AddRules(
     const std::string& extension_id,
     const std::vector<linked_ptr<Rule> >& rules) {
@@ skipping 294 matching lines @@
                  registry_,
                  extension_id,
                  base::Passed(&value)));
 
   waiting_for_extensions_.erase(extension_id);
 
   CheckIfReady();
 }
 
 }  // namespace extensions