Downloads: replace BrowserThread::FILE with task scheduler.

content/browser/download/save_file_manager.cc

Index: content/browser/download/save_file_manager.cc
diff --git a/content/browser/download/save_file_manager.cc b/content/browser/download/save_file_manager.cc
index 256ef2811375b0a4eaffbd3518fda580fdf0e5b7..ad12d8b5b455f6dec8dea485912043227cf80a74 100644
--- a/content/browser/download/save_file_manager.cc
+++ b/content/browser/download/save_file_manager.cc
@@ -13,6 +13,7 @@
 #include "base/strings/string_util.h"
 #include "base/threading/thread.h"
 #include "content/browser/child_process_security_policy_impl.h"
+#include "content/browser/download/download_task_runner.h"
 #include "content/browser/download/save_file.h"
 #include "content/browser/download/save_file_resource_handler.h"
 #include "content/browser/download/save_package.h"
@@ -59,19 +60,18 @@ SaveFileManager* SaveFileManager::Get() {
 // Called during the browser shutdown process to clean up any state (open files,
 // timers) that live on the saving thread (file thread).
 void SaveFileManager::Shutdown() {
-  BrowserThread::PostTask(
-      BrowserThread::FILE, FROM_HERE,
-      base::Bind(&SaveFileManager::OnShutdown, this));
+  GetDownloadTaskRunner()->PostTask(
+      FROM_HERE, base::Bind(&SaveFileManager::OnShutdown, this));
 }
 
 // Stop file thread operations.
 void SaveFileManager::OnShutdown() {
-  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK(GetDownloadTaskRunner()->RunsTasksInCurrentSequence());
   save_file_map_.clear();
 }
 
 SaveFile* SaveFileManager::LookupSaveFile(SaveItemId save_item_id) {
-  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK(GetDownloadTaskRunner()->RunsTasksInCurrentSequence());
   auto it = save_file_map_.find(save_item_id);
   return it == save_file_map_.end() ? nullptr : it->second.get();
 }
@@ -119,9 +119,8 @@ void SaveFileManager::SaveURL(SaveItemId save_item_id,
 
     // Since the data will come from render process, so we need to start
     // this kind of save job by ourself.
-    BrowserThread::PostTask(
-        BrowserThread::FILE, FROM_HERE,
-        base::Bind(&SaveFileManager::StartSave, this, info));
+    GetDownloadTaskRunner()->PostTask(
+        FROM_HERE, base::Bind(&SaveFileManager::StartSave, this, info));
   }
 }
 
@@ -160,18 +159,16 @@ SavePackage* SaveFileManager::GetSavePackageFromRenderIds(
 void SaveFileManager::DeleteDirectoryOrFile(const base::FilePath& full_path,
                                             bool is_dir) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  BrowserThread::PostTask(
-      BrowserThread::FILE, FROM_HERE,
-      base::Bind(&SaveFileManager::OnDeleteDirectoryOrFile,
-          this, full_path, is_dir));
+  GetDownloadTaskRunner()->PostTask(
+      FROM_HERE, base::Bind(&SaveFileManager::OnDeleteDirectoryOrFile, this,
+                            full_path, is_dir));
 }
 
 void SaveFileManager::SendCancelRequest(SaveItemId save_item_id) {
   // Cancel the request which has specific save id.
   DCHECK(!save_item_id.is_null());
-  BrowserThread::PostTask(
-      BrowserThread::FILE, FROM_HERE,
-      base::Bind(&SaveFileManager::CancelSave, this, save_item_id));
+  GetDownloadTaskRunner()->PostTask(
+      FROM_HERE, base::Bind(&SaveFileManager::CancelSave, this, save_item_id));
 }
 
 // Notifications sent from the IO thread and run on the file thread:
@@ -180,7 +177,7 @@ void SaveFileManager::SendCancelRequest(SaveItemId save_item_id) {
 // to create a SaveFile which will hold and finally destroy |info|. It will
 // then passes |info| to the UI thread for reporting saving status.
 void SaveFileManager::StartSave(SaveFileCreateInfo* info) {
-  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK(GetDownloadTaskRunner()->RunsTasksInCurrentSequence());
   DCHECK(info);
   // No need to calculate hash.
   std::unique_ptr<SaveFile> save_file = base::MakeUnique<SaveFile>(info, false);
@@ -204,7 +201,7 @@ void SaveFileManager::StartSave(SaveFileCreateInfo* info) {
 void SaveFileManager::UpdateSaveProgress(SaveItemId save_item_id,
                                          net::IOBuffer* data,
                                          int data_len) {
-  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK(GetDownloadTaskRunner()->RunsTasksInCurrentSequence());
   SaveFile* save_file = LookupSaveFile(save_item_id);
   if (save_file) {
     DCHECK(save_file->InProgress());
@@ -227,7 +224,7 @@ void SaveFileManager::SaveFinished(SaveItemId save_item_id,
   DVLOG(20) << __func__ << "() save_item_id = " << save_item_id
             << " save_package_id = " << save_package_id
             << " is_success = " << is_success;
-  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK(GetDownloadTaskRunner()->RunsTasksInCurrentSequence());
 
   int64_t bytes_so_far = 0;
   SaveFile* save_file = LookupSaveFile(save_item_id);
@@ -362,7 +359,7 @@ void SaveFileManager::ExecuteCancelSaveRequest(int render_process_id,
 // sent from the UI thread, the saving job may have already completed and
 // won't exist in our map.
 void SaveFileManager::CancelSave(SaveItemId save_item_id) {
-  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK(GetDownloadTaskRunner()->RunsTasksInCurrentSequence());
   auto it = save_file_map_.find(save_item_id);
   if (it != save_file_map_.end()) {
     std::unique_ptr<SaveFile> save_file = std::move(it->second);
@@ -392,7 +389,7 @@ void SaveFileManager::CancelSave(SaveItemId save_item_id) {
 
 void SaveFileManager::OnDeleteDirectoryOrFile(const base::FilePath& full_path,
                                               bool is_dir) {
-  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK(GetDownloadTaskRunner()->RunsTasksInCurrentSequence());
   DCHECK(!full_path.empty());
 
   base::DeleteFile(full_path, is_dir);
@@ -403,7 +400,7 @@ void SaveFileManager::RenameAllFiles(const FinalNamesMap& final_names,
                                      int render_process_id,
                                      int render_frame_routing_id,
                                      SavePackageId save_package_id) {
-  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK(GetDownloadTaskRunner()->RunsTasksInCurrentSequence());
 
   if (!resource_dir.empty() && !base::PathExists(resource_dir))
     base::CreateDirectory(resource_dir);
@@ -441,7 +438,7 @@ void SaveFileManager::OnFinishSavePageJob(int render_process_id,
 
 void SaveFileManager::RemoveSavedFileFromFileMap(
     const std::vector<SaveItemId>& save_item_ids) {
-  DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+  DCHECK(GetDownloadTaskRunner()->RunsTasksInCurrentSequence());
 
   for (const SaveItemId save_item_id : save_item_ids) {
     auto it = save_file_map_.find(save_item_id);