After y = -10 the heights of the screen edges darken

Summary:

When the player drops to -10 in height, his edges of the screen darken as if he is under bedrock. Screen edges don't darken in java version.

Steps to reproduce:

1. Drop down to -11 height.
2. Look down.

Observed results:

The edges of the screen darkened.

Expected results:

The edges of the screen will only darken under the bedrock.