scrollbars can be enabled per instance in 3 modes: always,never or when_needed 

instead of enableScrollbars (boolean value) this patch have 2 properties:
enableVerticalScrollbar  and enableHorizontalScrollbar 
those can be set with 3 constants uiGridConstants.scrollbars.ALWAYS,NEVER,WHEN_NEEDED

besides this there is also a small commit so that the horizontal scrollbar is also really in the view (just like the vertical)
instead of outside of the bounds.
For us that is really a problem because we wrap the grid i a div that won't show overflow, so the horizontal scrollbar is never shown.