hwc: Integerize in the outward direction of rectangle

Currently HWC integerizes float source co-ordinates (l, t, b, r) in
the inward direction, mimicking SF from pre-HWC-1.4. In case of
upscale where we need to create more destination pixels than incoming
ones, this chopping off can lead to quality issues, especially given
that the error magnification can be as much as 20x.

This change integerizes the source rectangle in the outward direction
which will help magnification cases. Downscale cases should be
unaffected since reduction hides errors, unlike magnification.

Change-Id: Ib72a1f8d52f4ec800387bfe2b91c9d3a65e6f557
1 file changed