Handle the case where IAttachmentExecute::Save() deletes a downloaded file.

content/browser/download/download_file.h

Index: content/browser/download/download_file.h
diff --git a/content/browser/download/download_file.h b/content/browser/download/download_file.h
index 22d646e96ba64d0a3bcde5a7977c13d16a1d2622..59a2e80b994b0fbec26a585e8bb074d536023da3 100644
--- a/content/browser/download/download_file.h
+++ b/content/browser/download/download_file.h
@@ -31,6 +31,11 @@ class CONTENT_EXPORT DownloadFile {
   typedef base::Callback<void(DownloadInterruptReason reason,
                               const FilePath& path)> RenameCompletionCallback;
 
+  // Callback used with Detach(). On success, |reason| will be
+  // DOWNLOAD_INTERRUPT_REASON_NONE.
+  typedef base::Callback<void(DownloadInterruptReason reason)>
+      DetachCompletionCallback;
+
   virtual ~DownloadFile() {}
 
   // Returns DOWNLOAD_INTERRUPT_REASON_NONE on success, or a network
@@ -49,14 +54,11 @@ class CONTENT_EXPORT DownloadFile {
 
   // Detach the file so it is not deleted on destruction.
   // |callback| will be called on the UI thread after detach.
-  virtual void Detach(base::Closure callback) = 0;
+  virtual void Detach(const DetachCompletionCallback& callback) = 0;
 
   // Abort the download and automatically close the file.
   virtual void Cancel() = 0;
 
-  // Informs the OS that this file came from the internet.
-  virtual void AnnotateWithSourceInformation() = 0;
-
   virtual FilePath FullPath() const = 0;
   virtual bool InProgress() const = 0;
   virtual int64 BytesSoFar() const = 0;