AU: Resume interrupted update attempts.

BUG=7390,7520
TEST=unit tests

Change-Id: I9baf72aa444dd855409f865f03fb665e91f8d03d

Review URL: http://codereview.chromium.org/3620013
diff --git a/download_action.h b/download_action.h
index 62dd29a..08035f0 100644
--- a/download_action.h
+++ b/download_action.h
@@ -93,6 +93,8 @@
     delegate_ = delegate;
   }
 
+  HttpFetcher* http_fetcher() { return http_fetcher_.get(); }
+
  private:
   // The InstallPlan passed in
   InstallPlan install_plan_;