Barrier blocks affect lighting and ambient occlusion

Partner Rank: 4
Verification builds: New beta 1.8 through 1.13.0.18
Summary: Barrier blocks can mess with the smooth lighting of adjacent blocks.
Use Case: We have an area where access is restricted with barriers at a certain time, then unrestricted after an event. It's intended that the player does not notice, but the lighting change makes the transition obvious and distracting.
Repro Steps:
1. Place a wall of light blocks (e.g. white concrete)
2. Place barrier blocks in front of some of the blocks, touching the ground
Observed Results: Shading gets weird where the barrier blocks are
Expected Results: Wall lighting is flush
Screenshots/Videos attached: Yes