This provides more realistic lighting with a very small performance cost.
The option is available in both GLES3 and GLES2, and can be enabled in
the Project Settings. This goes well with the ACES Fitted tonemapping mode
that was recently added.
When enabled, this also makes upgrading Godot 3.x projects to Godot 4.0 easier,
since lighting in 3.x will better match how it'll look in Godot 4.0.
85e080fcc0