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

content/browser/loader/url_loader_factory_impl.cc

Index: content/browser/loader/url_loader_factory_impl.cc
diff --git a/content/browser/loader/url_loader_factory_impl.cc b/content/browser/loader/url_loader_factory_impl.cc
index b9095b3a3aa2f845e3eb91db5717ff9351f0b5d5..851b564441975d0db642c621ffc627458f013ca5 100644
--- a/content/browser/loader/url_loader_factory_impl.cc
+++ b/content/browser/loader/url_loader_factory_impl.cc
@@ -5,11 +5,11 @@
 #include "content/browser/loader/url_loader_factory_impl.h"
 
 #include "base/memory/ptr_util.h"
+#include "content/browser/loader/loader_globals.h"
 #include "content/browser/loader/resource_dispatcher_host_impl.h"
 #include "content/browser/loader/resource_requester_info.h"
 #include "content/common/resource_request.h"
 #include "content/common/url_loader.mojom.h"
-#include "content/public/browser/browser_thread.h"
 #include "mojo/public/cpp/bindings/strong_binding.h"
 
 namespace content {
@@ -39,11 +39,13 @@ URLLoaderFactoryImpl::URLLoaderFactoryImpl(
     : requester_info_(std::move(requester_info)) {
   DCHECK((requester_info_->IsRenderer() && requester_info_->filter()) ||
          requester_info_->IsNavigationPreload());
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(
+      LoaderGlobals::Get()->io_thread_task_runner()->BelongsToCurrentThread());
 }
 
 URLLoaderFactoryImpl::~URLLoaderFactoryImpl() {
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(
+      LoaderGlobals::Get()->io_thread_task_runner()->BelongsToCurrentThread());
 }
 
 void URLLoaderFactoryImpl::CreateLoaderAndStart(
@@ -72,7 +74,8 @@ void URLLoaderFactoryImpl::CreateLoaderAndStart(
     int32_t request_id,
     const ResourceRequest& url_request,
     mojom::URLLoaderClientPtr client) {
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(
+      LoaderGlobals::Get()->io_thread_task_runner()->BelongsToCurrentThread());
 
   ResourceDispatcherHostImpl* rdh = ResourceDispatcherHostImpl::Get();
   rdh->OnRequestResourceWithMojo(requester_info, routing_id, request_id,
@@ -86,7 +89,8 @@ void URLLoaderFactoryImpl::SyncLoad(ResourceRequesterInfo* requester_info,
                                     int32_t request_id,
                                     const ResourceRequest& url_request,
                                     const SyncLoadCallback& callback) {
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(
+      LoaderGlobals::Get()->io_thread_task_runner()->BelongsToCurrentThread());
 
   ResourceDispatcherHostImpl* rdh = ResourceDispatcherHostImpl::Get();
   rdh->OnSyncLoadWithMojo(requester_info, routing_id, request_id, url_request,