Reduce/remove usage of BrowserThread in content/browser/loader.

content/browser/loader/resource_hints_impl.cc

 // Copyright 2016 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 <string>
 
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
-#include "content/public/browser/browser_thread.h"
+#include "content/browser/loader/resource_dispatcher_host_impl.h"
 #include "content/public/browser/resource_context.h"
 #include "content/public/browser/resource_hints.h"
 #include "net/base/address_list.h"
 #include "net/base/load_flags.h"
 #include "net/dns/host_resolver.h"
 #include "net/http/http_network_session.h"
 #include "net/http/http_request_info.h"
 #include "net/http/http_stream_factory.h"
 #include "net/http/http_transaction_factory.h"
 #include "net/log/net_log_with_source.h"
@@ skipping 24 matching lines @@
 }
 
 }  // namespace
 
 void PreconnectUrl(content::ResourceContext* resource_context,
                    const GURL& url,
                    const GURL& first_party_for_cookies,
                    int count,
                    bool allow_credentials,
                    net::HttpRequestInfo::RequestMotivation motivation) {
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(ResourceDispatcherHostImpl::Get()
+             ->io_thread_task_runner()
+             ->BelongsToCurrentThread());
   DCHECK(resource_context);
 
   net::URLRequestContext* context = resource_context->GetRequestContext();
   net::HttpTransactionFactory* factory = context->http_transaction_factory();
   net::HttpNetworkSession* session = factory->GetSession();
 
   std::string user_agent;
   if (context->http_user_agent_settings())
     user_agent = context->http_user_agent_settings()->GetUserAgent();
   net::HttpRequestInfo request_info;
@@ skipping 17 matching lines @@
                               net::LOAD_DO_NOT_SEND_AUTH_DATA;
   }
 
   net::HttpStreamFactory* http_stream_factory = session->http_stream_factory();
   http_stream_factory->PreconnectStreams(count, request_info);
 }
 
 int PreresolveUrl(content::ResourceContext* resource_context,
                   const GURL& url,
                   const net::CompletionCallback& callback) {
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(ResourceDispatcherHostImpl::Get()
+             ->io_thread_task_runner()
+             ->BelongsToCurrentThread());
   DCHECK(resource_context);
 
   auto request_holder = base::MakeUnique<RequestHolder>();
   auto addresses = base::MakeUnique<net::AddressList>();
 
   // Save raw pointers before the unique_ptr is invalidated by base::Passed.
   net::AddressList* raw_addresses = addresses.get();
   std::unique_ptr<net::HostResolver::Request>* out_request =
       request_holder->GetRequest();
 
   net::HostResolver* resolver = resource_context->GetHostResolver();
   net::HostResolver::RequestInfo resolve_info(net::HostPortPair::FromURL(url));
   resolve_info.set_is_speculative(true);
   return resolver->Resolve(
       resolve_info, net::IDLE, raw_addresses,
       base::Bind(&OnResolveComplete, base::Passed(&request_holder),
                  base::Passed(&addresses), callback),
       out_request, net::NetLogWithSource());
 }
 
 }  // namespace content