Fix viewport width & height when frozen rows and columns are not enabled.
Fix viewport width & height when frozen rows and columns are not enabled.

dynamicaction/SlickGrid,dynamicaction/SlickGrid,chrisghost/X-SlickGrid,Revionics/SlickGrid,ddomingues/X-SlickGrid,Revionics/SlickGrid,ddomingues/X-SlickGrid,chrisghost/X-SlickGrid