Tweak comments and put in tests for ignoring safe browsing results.

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 9ec4cb54839bc83a21a19fd40b300018077be25c..5333938c3db9f338ec3c8d7fd350759992f027ce 100644
--- a/content/public/browser/download_manager_delegate.h
+++ b/content/public/browser/download_manager_delegate.h
@@ -85,9 +85,9 @@ class CONTENT_EXPORT DownloadManagerDelegate {
   // Allows the delegate to delay completion of the download.  This function
   // will either return true (in which case the download may complete)
   // or will call the callback passed when the download is ready for
-  // completion.  This routine may be called multiple times; once it has
-  // returned true for a particular download it should continue to return
-  // true for that download.
+  // completion.  This routine may be called multiple times; once the callback
+  // has been called or the function has returned true for a particular
+  // download it should continue to return true for that download.
   virtual bool ShouldCompleteDownload(
       DownloadItem* item,
       const base::Closure& complete_callback);