Use TaskScheduler instead of blocking pool in profile_impl_io_data.cc.

chrome/browser/profiles/profile_impl_io_data.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/profiles/profile_impl_io_data.h"
 
 #include <memory>
 #include <set>
 #include <string>
 #include <utility>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/field_trial.h"
 #include "base/sequenced_task_runner.h"
 #include "base/stl_util.h"
 #include "base/strings/string_util.h"
+#include "base/task_scheduler/post_task.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/custom_handlers/protocol_handler_registry.h"
 #include "chrome/browser/custom_handlers/protocol_handler_registry_factory.h"
 #include "chrome/browser/data_use_measurement/chrome_data_use_ascriber.h"
 #include "chrome/browser/io_thread.h"
 #include "chrome/browser/net/chrome_network_delegate.h"
 #include "chrome/browser/net/http_server_properties_manager_factory.h"
@@ skipping 464 matching lines @@
       profile_params->cookie_monster_delegate.get());
   cookie_config.crypto_delegate = cookie_config::GetCookieCryptoDelegate();
   main_context_storage->set_cookie_store(
       content::CreateCookieStore(cookie_config));
 
   // Set up server bound cert service.
   DCHECK(!lazy_params_->channel_id_path.empty());
   scoped_refptr<QuotaPolicyChannelIDStore> channel_id_db =
       new QuotaPolicyChannelIDStore(
           lazy_params_->channel_id_path,
-          BrowserThread::GetBlockingPool()->GetSequencedTaskRunner(
-              base::SequencedWorkerPool::GetSequenceToken()),
+          base::CreateSequencedTaskRunnerWithTraits(
+              base::TaskTraits().MayBlock().WithPriority(
+                  base::TaskPriority::BACKGROUND)),

[gab, 2017/08/15 00:02:44]

This call also lands in net::SQLiteChannelIDStore's constructor

           lazy_params_->special_storage_policy.get());
   main_context_storage->set_channel_id_service(
       base::MakeUnique<net::ChannelIDService>(
           new net::DefaultChannelIDStore(channel_id_db.get())));
 
   main_context->cookie_store()->SetChannelIDServiceID(
       main_context->channel_id_service()->GetUniqueID());
 
   std::unique_ptr<net::HttpCache::BackendFactory> main_backend(
       new net::HttpCache::DefaultBackend(
@@ skipping 123 matching lines @@
 
     // TODO(creis): We should have a cookie delegate for notifying the cookie
     // extensions API, but we need to update it to understand isolated apps
     // first.
     content::CookieStoreConfig cookie_config(
         cookie_path, content::CookieStoreConfig::EPHEMERAL_SESSION_COOKIES,
         nullptr, nullptr);
     cookie_config.crypto_delegate = cookie_config::GetCookieCryptoDelegate();
     cookie_store = content::CreateCookieStore(cookie_config);
     channel_id_db = new net::SQLiteChannelIDStore(
-        channel_id_path,
-        BrowserThread::GetBlockingPool()->GetSequencedTaskRunner(
-            base::SequencedWorkerPool::GetSequenceToken()));
+        channel_id_path, base::CreateSequencedTaskRunnerWithTraits(
+                             base::TaskTraits().MayBlock().WithPriority(
+                                 base::TaskPriority::BACKGROUND)));

[gab, 2017/08/15 00:02:44]

I don't think TaskPriority::BACKGROUND is correct here, although
net::SQLiteChannelIDStore()'s API states that this is its "background task
runner", it also states it uses it for all I/O operations. This is tied to the
cookie store and I assume some of these I/O operations will include reads for
user visible content.

   }
   std::unique_ptr<net::ChannelIDService> channel_id_service(
       new net::ChannelIDService(
           new net::DefaultChannelIDStore(channel_id_db.get())));
   cookie_store->SetChannelIDServiceID(channel_id_service->GetUniqueID());
 
   // Build a new HttpNetworkSession that uses the new ChannelIDService.
   // TODO(mmenke):  It weird to combine state from
   // main_request_context_storage() objects and the argumet to this method,
   // |main_context|.  Remove |main_context| as an argument, and just use
@@ skipping 124 matching lines @@
     const base::Closure& completion) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   DCHECK(initialized());
 
   DCHECK(transport_security_state());
   // Completes synchronously.
   transport_security_state()->DeleteAllDynamicDataSince(time);
   DCHECK(http_server_properties_manager_);
   http_server_properties_manager_->Clear(completion);
 }