Off streen rendering may lead to broken chart

Steps to reproduce:
1. Prepare an inquiry (with a chart)
2. Re-open Sqliteviz
3. Load a database and open inquiry 
4. Hide another panel (i.e. leave only SQL one)
5. Run the query
6. Switch the SQL panel to chart panel

Expected result:

- Chart is rendered correctly.

Actual result:

- Chart is rendered incorrectly.