Blocks with subsurface scattering enabled cause height maps to ignore player shadows from sun

Block height maps ignore player casted shadows from the sun in the deferred rendering technical preview when enabling subsurface scattering on that block.

Reproduce:

1. Import the attached resource pack (it has a on and off mode in pack settings for comparison).

2. Enable subsurface scattering in the pack settings (on by default) place a grass block and set the time to day, you will see that the height maps ignore player shadows from the sun when the block has subsurface scattering enabled.

Observed: 

Block height map texture is still illuminated with a player shadow when standing on a block with subsurface scattering enabled.

Expected: 

Height map texture should be affected by player shadows, making it just as dark as the shadows from a block.