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

content/browser/loader/temporary_file_stream.cc

Index: content/browser/loader/temporary_file_stream.cc
diff --git a/content/browser/loader/temporary_file_stream.cc b/content/browser/loader/temporary_file_stream.cc
index 74ca4920b4a76cf696fb2421491118880c8d7e1d..7557bd690c566c1715876420e0963850183d5b51 100644
--- a/content/browser/loader/temporary_file_stream.cc
+++ b/content/browser/loader/temporary_file_stream.cc
@@ -10,6 +10,7 @@
 #include "base/callback.h"
 #include "base/files/file_proxy.h"
 #include "base/memory/ref_counted.h"
+#include "content/browser/loader/loader_globals.h"
 #include "content/public/browser/browser_thread.h"
 #include "net/base/file_stream.h"
 #include "storage/browser/blob/shareable_file_reference.h"
@@ -24,7 +25,8 @@ void DidCreateTemporaryFile(const CreateTemporaryFileStreamCallback& callback,
                             std::unique_ptr<base::FileProxy> file_proxy,
                             base::File::Error error_code,
                             const base::FilePath& file_path) {
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(
+      LoaderGlobals::Get()->io_thread_task_runner()->BelongsToCurrentThread());
 
   if (!file_proxy->IsValid()) {
     callback.Run(error_code, std::unique_ptr<net::FileStream>(), NULL);
@@ -51,7 +53,8 @@ void DidCreateTemporaryFile(const CreateTemporaryFileStreamCallback& callback,
 
 void CreateTemporaryFileStream(
     const CreateTemporaryFileStreamCallback& callback) {
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(
+      LoaderGlobals::Get()->io_thread_task_runner()->BelongsToCurrentThread());

[jam, 2017/03/29 15:44:33]

this is only called by redirect_to_file_resource_handler.cc which isn't planned
to move, so it can use BrowserThread

[ananta, 2017/03/29 19:41:04]

Done.

 
   std::unique_ptr<base::FileProxy> file_proxy(new base::FileProxy(
       BrowserThread::GetTaskRunnerForThread(BrowserThread::FILE).get()));