PlzNavigate: add support in several navigation controller unit tests

content/browser/frame_host/navigator_impl.cc

Index: content/browser/frame_host/navigator_impl.cc
diff --git a/content/browser/frame_host/navigator_impl.cc b/content/browser/frame_host/navigator_impl.cc
index c72230c838a9e94383d93e2407c4d2c3af884899..8fbc2c23bae8e728389074d34a2bf36e03b32e08 100644
--- a/content/browser/frame_host/navigator_impl.cc
+++ b/content/browser/frame_host/navigator_impl.cc
@@ -883,10 +883,12 @@ bool NavigatorImpl::RequestNavigation(
   navigation_request_map_.set(frame_tree_node_id, navigation_request.Pass());
 
   if (frame_tree_node->current_frame_host()->IsRenderFrameLive()) {
+    NavigationRequest* request_to_send =
+        navigation_request_map_.get(frame_tree_node_id);
     frame_tree_node->current_frame_host()->Send(new FrameMsg_RequestNavigation(
         frame_tree_node->current_frame_host()->GetRoutingID(),
-        navigation_request_map_.get(frame_tree_node_id)->common_params(),
-        request_params));
+        request_to_send->common_params(), request_params));
+    request_to_send->SetWaitingForRendererResponse();
     return true;
   }