DownloadManagerDelegate::ShouldCompleteDownload(callback)

chrome/browser/chromeos/gdata/gdata_download_observer.h

Index: chrome/browser/chromeos/gdata/gdata_download_observer.h
diff --git a/chrome/browser/chromeos/gdata/gdata_download_observer.h b/chrome/browser/chromeos/gdata/gdata_download_observer.h
index 3701c7201781d855b855b5a3160997917e67e54c..3567dc91f895e37ceeec28556a9a16f3142a6f5d 100644
--- a/chrome/browser/chromeos/gdata/gdata_download_observer.h
+++ b/chrome/browser/chromeos/gdata/gdata_download_observer.h
@@ -44,8 +44,16 @@ class GDataDownloadObserver : public content::DownloadManager::Observer,
   // Checks if |download| is ready to complete. Returns true if |download| has
   // no GData upload associated with it or if the GData upload has already
   // completed. This method is called by the ChromeDownloadManagerDelegate to
-  // check if the download is ready to complete.
-  static bool IsReadyToComplete(content::DownloadItem* download);
+  // check if the download is ready to complete.  If the download is not yet
+  // ready to complete and |complete_callback| is not null, then
+  // |complete_callback| will be called on the UI thread when the download
+  // becomes ready to complete.  If this call is made multiple times with the
+  // download not ready to complete, only one callback will be generated, to the
+  // last non-null value passed as complete_callback.  You can't unset it once
+  // you set it, except to reset it to another non-null callback.
+  static bool IsReadyToComplete(
+      content::DownloadItem* download,
+      const base::Closure& complete_callback);
 
   // Returns the count of bytes confirmed as uploaded so far for |download|.
   static int64 GetUploadedBytes(content::DownloadItem* download);