On tablet, if splitting touch controls, I only get 5 item spaces instead of 7 if not splitting

This happens in all versions, 0.7.6 and even in 0.8.0 build 7. If I play on my tablet without split touch controls, i get 7 spaces in items bar. If I split them, I only get 5(after restarting game).

What I expected to happen was to have 7 spaces.
When I split controls, I should still have 7 ( I,d like even more, but 7 is what works without splitting touch). I have 5 instead. If I open minecraft without splitting controls and then split them in-game, I have 7 slots.

Steps to Reproduce:
1. Open minecraft with split touch controls(little cross in the middle for aiming)
2. Open any world, creative or survival.
3. Only 5 item slots on 7" tablet.