Fix various issues in RedirectToFileResourceHandler.

content/browser/loader/sync_resource_handler.cc

Index: content/browser/loader/sync_resource_handler.cc
diff --git a/content/browser/loader/sync_resource_handler.cc b/content/browser/loader/sync_resource_handler.cc
index 865b29e404e0c1e276535bf759d4a55108d17c33..e39ae1c7d46241e366da2776938fa4ad8a7fe9f0 100644
--- a/content/browser/loader/sync_resource_handler.cc
+++ b/content/browser/loader/sync_resource_handler.cc
@@ -86,6 +86,18 @@ bool SyncResourceHandler::OnResponseStarted(
 
   DevToolsNetLogObserver::PopulateResponseInfo(request(), response);
 
+  // If the parent handler downloaded the resource to a file, grant the child
+  // read permissions on it. Note: there is similar logic in
+  // AsyncResourceHandler.
+  //
+  // TODO(davidben): Can we remove support for download_file in sync requests
+  // altogether? I don't think Blink ever makes such requests.
+  if (!response->head.download_file_path.empty()) {
+    rdh_->RegisterDownloadedTempFile(
+        info->GetChildID(), info->GetRequestID(),
+        response->head.download_file_path);
+  }
+
   // We don't care about copying the status here.
   result_.headers = response->head.headers;
   result_.mime_type = response->head.mime_type;