Create base::WorkerPoolJob. Use it for HostResolverImpl and DirectoryLister.

chrome/browser/file_select_helper.cc

Index: chrome/browser/file_select_helper.cc
diff --git a/chrome/browser/file_select_helper.cc b/chrome/browser/file_select_helper.cc
index 1604b0de89c18e97e36566fdfaa5f235c0f2e038..8f6399dffe8cc1773fcef76c3b107b481d2fd9e5 100644
--- a/chrome/browser/file_select_helper.cc
+++ b/chrome/browser/file_select_helper.cc
@@ -12,6 +12,7 @@
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "net/base/mime_util.h"
+#include "net/base/net_errors.h"
 #include "chrome/browser/platform_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/renderer_host/render_view_host.h"
@@ -34,12 +35,6 @@ FileSelectHelper::~FileSelectHelper() {
   // away so they don't try and call back to us.
   if (select_file_dialog_.get())
     select_file_dialog_->ListenerDestroyed();
-
-  // Stop any pending directory enumeration and prevent a callback.
-  if (directory_lister_.get()) {
-    directory_lister_->set_delegate(NULL);
-    directory_lister_->Cancel();
-  }
 }
 
 void FileSelectHelper::FileSelected(const FilePath& path,
@@ -86,16 +81,15 @@ void FileSelectHelper::FileSelectionCanceled(void* params) {
 }
 
 void FileSelectHelper::DirectorySelected(const FilePath& path) {
-  directory_lister_ = new net::DirectoryLister(path,
-                                               true,
-                                               net::DirectoryLister::NO_SORT,
-                                               this);
-  if (!directory_lister_->Start())
-    FileSelectionCanceled(NULL);
+  directory_lister_.reset(
+      new net::DirectoryLister(path,
+                               true,
+                               net::DirectoryLister::NO_SORT,
+                               this));
+  directory_lister_->Start();
 }
 
-void FileSelectHelper::OnListFile(
-    const net::DirectoryLister::DirectoryListerData& data) {
+void FileSelectHelper::OnListFile(const net::DirectoryLister::Data& data) {
   // Directory upload only cares about files.  This util call just checks
   // the flags in the structure; there's no file I/O going on.
   if (file_util::FileEnumerator::IsDirectory(data.info))
@@ -108,14 +102,14 @@ void FileSelectHelper::OnListDone(int error) {
   if (!render_view_host_)
     return;
 
-  if (error) {
+  if (error != net::OK) {
     FileSelectionCanceled(NULL);
     return;
   }
 
   render_view_host_->FilesSelectedInChooser(directory_lister_results_);
   render_view_host_ = NULL;
-  directory_lister_ = NULL;
+  directory_lister_.reset();
   directory_lister_results_.clear();
 }