Add prefetch support to AffiliationBackend.

components/password_manager/core/browser/affiliation_service.cc

 // 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 "components/password_manager/core/browser/affiliation_service.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/files/file_path.h"
 #include "base/location.h"
@@ skipping 38 matching lines @@
     const ResultCallback& result_callback) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(backend_);
   backend_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&AffiliationBackend::GetAffiliations,
                  base::Unretained(backend_), facet_uri, cached_only,
                  result_callback, base::ThreadTaskRunnerHandle::Get()));
 }
 
-AffiliationService::CancelPrefetchingHandle AffiliationService::Prefetch(
-    const FacetURI& facet_uri,
-    const base::Time& keep_fresh_until) {
+void AffiliationService::Prefetch(const FacetURI& facet_uri,
+                                  const base::Time& keep_fresh_until) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(backend_);
   backend_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&AffiliationBackend::Prefetch, base::Unretained(backend_),
                  facet_uri, keep_fresh_until));
-  return base::Bind(&AffiliationService::CancelPrefetch,
-                    weak_ptr_factory_.GetWeakPtr(), facet_uri,
-                    keep_fresh_until);
 }
 
 void AffiliationService::CancelPrefetch(const FacetURI& facet_uri,
                                         const base::Time& keep_fresh_until) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(backend_);
   backend_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&AffiliationBackend::CancelPrefetch,
                  base::Unretained(backend_), facet_uri, keep_fresh_until));
 }
 
 void AffiliationService::TrimCache() {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(backend_);
   backend_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&AffiliationBackend::TrimCache, base::Unretained(backend_)));
 }
 
 }  // namespace password_manager