[downloads] Move platform specific code out of DownloadTargetDeterminer.

content/public/browser/download_manager_delegate.h

Index: content/public/browser/download_manager_delegate.h
diff --git a/content/public/browser/download_manager_delegate.h b/content/public/browser/download_manager_delegate.h
index 2c91638b118fddf902bb49f7eb12853cfc9f8481..f0dd795e870a814ea246d538e936b3415ac8607b 100644
--- a/content/public/browser/download_manager_delegate.h
+++ b/content/public/browser/download_manager_delegate.h
@@ -34,17 +34,32 @@ typedef base::Callback<void(const base::FilePath&,
                             const SavePackageDownloadCreatedCallback&)>
     SavePackagePathPickedCallback;
 
-// Called with the results of DetermineDownloadTarget(). If the delegate decides
-// to cancel the download, then |target_path| should be set to an empty path. If
-// |target_path| is non-empty, then |intermediate_path| is required to be
-// non-empty and specify the path to the intermediate file (which could be the
-// same as |target_path|). Both |target_path| and |intermediate_path| are
-// expected to in the same directory.
-typedef base::Callback<void(
-    const base::FilePath& target_path,
-    DownloadItem::TargetDisposition disposition,
-    DownloadDangerType danger_type,
-    const base::FilePath& intermediate_path)> DownloadTargetCallback;
+// Called with the results of DetermineDownloadTarget().
+//
+// |interrupt_reason| should be set to DOWNLOAD_INTERRUPT_REASON_NONE in
+//     order to proceed with the download. DOWNLOAD_INTERRUPT_REASON_USER_CANCEL
+//     results in the download being marked cancelled. Any other value results
+//     in the download being marked as interrupted. The other fields are only
+//     considered valid if |interrupt_reason| is NONE.
+//
+// |target_path| should be set to a non-empty path which is taken to be the
+//     final target path for the download. Any file already at this path will be
+//     overwritten.
+//
+// |intermediate_path| specifies the path to the intermediate file. The download
+//     will be written to this path until all the bytes have been written. Upon
+//     completion, the file will be renamed to |target_path|.
+//     |intermediate_path| could be the same as |target_path|. Both paths must
+//     be in the same directory.
+//
+// |disposition| and |danger_type| are attributes associated with the download
+//     item and can be accessed via the DownloadItem accessors.
+typedef base::Callback<void(const base::FilePath& target_path,
+                            DownloadItem::TargetDisposition disposition,
+                            DownloadDangerType danger_type,
+                            const base::FilePath& intermediate_path,
+                            DownloadInterruptReason interrupt_reason)>
+    DownloadTargetCallback;
 
 // Called when a download delayed by the delegate has completed.
 typedef base::Callback<void(bool)> DownloadOpenDelayedCallback;