Allow top-level navigation in extension pop-ups if it only triggers a download.

content/browser/frame_host/navigation_request.cc

Index: content/browser/frame_host/navigation_request.cc
diff --git a/content/browser/frame_host/navigation_request.cc b/content/browser/frame_host/navigation_request.cc
index 63679331dcc375c897e23237f57d72e9cde4d39a..ba5c5a5c74aae75f748ab7ec8017c573402e3a25 100644
--- a/content/browser/frame_host/navigation_request.cc
+++ b/content/browser/frame_host/navigation_request.cc
@@ -359,9 +359,8 @@ void NavigationRequest::OnResponseStarted(
   // renderer, allow the embedder to cancel the transfer.
   if (!browser_initiated_ &&
       render_frame_host != frame_tree_node_->current_frame_host() &&
-      !frame_tree_node_->navigator()
-           ->GetDelegate()
-           ->ShouldTransferNavigation()) {
+      !frame_tree_node_->navigator()->GetDelegate()->ShouldTransferNavigation(
+          frame_tree_node_->IsMainFrame())) {
     frame_tree_node_->ResetNavigationRequest(false);
     return;
   }