Use output device scaling to determine cells in draw-area.

Change-Id: Idf4e6ccb72090a55b6a9234cafae21821e3df0b0
Set correct scaling for normal painting.

As we no longer read the scaling from the viewdata, we should
instead set it on the output device when doing normal rendering.

However the grid still doesn't exactly match the external axes yet,
there are probably more rounding errors wherever they are painted.

Change-Id: I25b1bd9b344115578fe892aa94fbf753a3c10c81
Revert "Use output device scaling to determine cells in draw-area."

This reverts commit 9fd5c03c80f92aabfd0cbf91fa80a811518995bd.