Support scoped_ptr in BrowserThread::DeleteOnThread.

chrome/browser/local_discovery/pwg_raster_converter.cc

Index: chrome/browser/local_discovery/pwg_raster_converter.cc
diff --git a/chrome/browser/local_discovery/pwg_raster_converter.cc b/chrome/browser/local_discovery/pwg_raster_converter.cc
index 9ae1d06379c1c51a5b4217d6861b0d1e34e11595..711c9ce1ab32d9983f52f3ffefb056fd7f75bafd 100644
--- a/chrome/browser/local_discovery/pwg_raster_converter.cc
+++ b/chrome/browser/local_discovery/pwg_raster_converter.cc
@@ -127,7 +127,7 @@ class PwgUtilityProcessHostClient : public content::UtilityProcessHostClient {
   void RunCallbackOnUIThread(bool success);
   void OnFilesReadyOnUIThread();
 
-  scoped_ptr<FileHandlers> files_;
+  scoped_ptr<FileHandlers, BrowserThread::DeleteOnFileThread> files_;
   printing::PdfRenderSettings settings_;
   printing::PwgRasterSettings bitmap_settings_;
   PWGRasterConverter::ResultCallback callback_;
@@ -142,8 +142,6 @@ PwgUtilityProcessHostClient::PwgUtilityProcessHostClient(
     : settings_(settings), bitmap_settings_(bitmap_settings) {}
 
 PwgUtilityProcessHostClient::~PwgUtilityProcessHostClient() {
-  // Delete temp directory.
-  BrowserThread::DeleteSoon(BrowserThread::FILE, FROM_HERE, files_.release());
 }
 
 void PwgUtilityProcessHostClient::Convert(