This adds an option for the HDRI rotation to follow the view rotation.
When this option is enabled, this allows EEVEE materials to be used as
matcaps for sculpting and painting.
This has an extra performance cost when orbiting around the model as the
lookdev cache needs to be recalculated, but in my test it is barely
noticeable.
Reviewed By: fclem
Differential Revision: https://developer.blender.org/D8566
5855f317a7