Zeppelin reload note from storage doesn't work

Version affected 

+ I'm rebuild and use Zeppelin 0.9.0 RC1 for the test situation 

Issue description 

+ When user login to the home page and click on "Reload notes from storage"; the notes list is not refreshed

How to recreate the issue

+ Come to Zeppelin home page -> "Create new note" -> Naming it as your choice. My case is "RandomNoteToDelete" 
+ Visit the Notebook Repos to find the repo location

+ cd to this repo path and delete the recently created notebook. In my case, command is like this

cd /notebook_repo_path/
ls -ltr | grep RandomNoteToDelete
rw-rw-r- 1 huynguyen huynguyen 683 Dec 17 04:50 RandomNoteToDelete_2FTJQDUXA.zpln

rm RandomNoteToDelete_2FTJQDUXA.zpln

 + Come back to the Zeppelin Homepage -> click on the "Reload notes from storage" button. -> The notebook RandomNoteToDelete is still there no matter how many times you click  

Other notes
+ The same thing happens when you copy a new notebook into the repo path. The reload feature doesn't work and zeppelin notebook can't recognize new notebook

+ When I restart the Zeppelin notebook, it then can recognize the notebook changes. But again, using reload button doesn't work as before